I am someone who primarily plays Japanese mahjong, but over the past year or so I've become increasingly interested in other forms of mahjong, if only to see what variety exists out there. In this time, I've had the chance to play Singapore-style online, whether against computers or human opponents (on Viwawa if you know that site), and I just wanted to ask someone more familiar with the game to see if my observations are at all accurate.
Coming from Japanese-style, I find the most significant difference to not be so much the lack of riichi or even the animal tiles (though they do contribute to a different experience), but the relative lack of low fan/tai hands. Things like tanyao (all simples) and iipeikou (two of the same sequence) don't exist in Singapore mahjong, and so I feel like the hands are more inflexible, that they don't flow into each other quite as easily.
As a result, it seems like you have to decide from the very beginning where you want your hand to go and that, unless you draw a relevant bonus tile, you have to stick to your path much more diligently, whether that's an all sequences hand or starting out with two honor tiles and planning around getting the third or aiming for a half flush.
I see that there is the possibiliy of increasing the tai minimum in order to make the game more challenging, but my opinion (based on my limited experience) is that high tai requirements are not suitable for Singapore Mahjong because of the relatively small amount of available hands. Unlike MCR especially where there are so many hands that you can realistically stack many of them together to meet more difficult fan requirements, I feel like anything more than a 2 tai minimum in Singapore Mahjong may make the game overly stiff and unwieldy, though whether the minimum is better at 1 or 2 is something I'm undecided on.
Anyway, thanks for hearing me out. I don't pretend to be an expert in even my own preferred mahjong, so I'm looking forward to a response.
A most interesting comment, with some interesting points to discuss! Below, I have laid out my thoughts and views in response to ogiuemaniax's comment. By no means are these points conclusive and definitive; there is a lot of scope for discussion.
1. Significant differences between Japanese riichi majan and Singapore Style mahjong.
I find it actually difficult to articulate the significant difference because Japanese riichi majan and Singapore Style mahjong are so different but yet still quite similar. I will try to discuss this point from a historical perspective.
Essentially, Japanese riichi majan and Singapore Style mahjong evolved from what is known as Chinese Classical, but in different ways. Both variants actually retain many features of Chinese Classical; we can compare this to variants such as American mah jongg (almost no resemblance to any other variant of mahjong anymore!), MCR, and Taiwanese. However, I view Singapore Style to be more conservative, and this includes the retention of most, if not all, of the traditional scoring elements found in Chinese Classical, whereas Japanese riichi majan innovated many new scoring elements (examples ogiuemaniax brought up include tanyao and iipeikou). Many of the newer styles of mahjong (e.g. Shanghainese, Hong Kong New Style, MCR, Zung Jung) have similar/identical innovations pertaining to new scoring elements. Singapore Style and Hong Kong Old Style, by contrast, use few, if any, new scoring elements beyond those inherited from Chinese Classical.
Because there are many more ways to obtain higher scores through hand manipulation, rather than through sheer luck (say, through the drawing of bonus tiles), Japanese riichi majan, MCR, Zung Jung have all developed to emphasise hand-construction and to de-emphasise luck. This is the reason, perhaps, why Japanese riichi majan use no flowers. Contrastingly, Singapore Style mahjong added four more bonus tiles. This makes obtaining the minimum of one double (one tai) relatively easier, and drawing more useful bonus tiles is not that difficult. In terms of play, a Singapore Style player can expect to win a lot of hands with one double, two doubles, three doubles, just using the bonus tiles alone.
So, if you were to ask me, the significant difference between Japanese riichi majan and Singapore Style mahjong is then not truly about the relative lack of low-value scoring elements, but the presence or absence of bonus tiles that fulfil the role of obligatory scoring element (i.e. the equivalent of yaku, not han). Since there are no bonus tiles that easily allow any player to meet the minimum requirement to win in Japanese riichi majan, the player is forced to use any of the available yaku to compete for the win. By necessity, a lot more yaku had been developed to allow the player more opportunities to complete the hand.
2. Flexibility and hand development
Well, it is true that without bonus tiles, the hand development in Singapore Style mahjong usually takes only one of three paths: All Chows (pinghu), All Pungs, and Mixed Suit/Half Flush. But this is not really very different from Japanese riichi majan. I doubt it is easy to 'flow' from an opened hand with a pung of Seat Wind back into something else other than All Pungs and/or Half Flush anyway. People tend to think of Japanese riichi majan as 'flexible' but only if the hand remains concealed (which then allow the completion of obligatorily concealed scoring elements such as riichi, pinfu, menzen, iipeikou etc. and some optionally concealed scoring elements). Singapore Style mahjong is as flexible as most other variants; opening up a hand always create a loss of flexibility. It is less of a hindrance in Singapore Style mahjong though, since bonus tiles usually shoulder the requirement for more doubles for high-scoring wins.
3. Scoring system dictates the strategy
Sometimes, it is rather difficult to compare different styles of mahjong. The very differences in the scoring system will create different conditions that then constrain the kinds of strategies usable. Singapore Style mahjong does not require the kind of flexibility demanded in Japanese riichi majan. If a player who is used to a style of play best suited for Japanese riichi majan play that way in Singapore Style mahjong, then he may not be able to do well. Since there is no restriction on concealment for pinghu in Singapore Style, players will readily open their hands to take chows to quickly advance their hands towards completion (moreso if such players have not drawn any bonus tiles and wish to aim for a 4-double pinghu win). The presence of bonus tiles affects the strategies of players in Singapore Style and cannot be discounted.
4. Minimum and maximum
Actually, as typically played in Singapore, a minimum of one double and a maximum of five doubles is 'standard' (well, 'standard' means 'very common' here) after decades of game evolution and equilibrium. The scoring system (with all the associated bao penalties etc.) have stabilised to be most balanced under the conditions of a minimum of one double and a maximum of five doubles.
If there is no minimum (thus allowing Chicken Hands), then there is not enough challenge for players; to meet a minimum of one double, players must know how to construct a pinghu hand correctly in the absence of a valid bonus tile. If the minimum is raised to two doubles, players cannot pre-empt dangerous players late-game with a cheap one-double pinghu hand; therefore any minimum above one double is typically unpopular with the more experienced and expert players.
The maximum of five doubles fits nicely with limiting the role of luck (especially for luck-based limit hands like Heavenly Win, Eight Flowers etc.), and at the same time making the role of bao penalties relevant and interesting. If the limit is too high, say, at 8 doubles, then a baoda penalty, where a player becomes penalised for discarding a tile allowing a dangerous player to go from 7 to 8 doubles (i.e. to reach the Limit; based on the exposed bonus tiles and Honour tile melds on the tables) becomes all too rare and thus pointless. It is common to see 4 doubles on the table, so a baoda penalty is quite likely in such situations; much less common to see 7 doubles on the table.
ogiuemaniax, I hope this answers your query in some part. Feel free to carry on this discussion with your comments.