Reachmahjong.com

Here I go again.
Seems like offense is okay this time around. The big issue is that the hand doesn't have a pair yet (well, not an isolated one, anyways). I'd discard the , and leave in the possibility for Iipeikou and San Shoku Dojun (thank's for the guide, Barticle!).
You're 1 away from tempai, waiting on , , , or to get into tempai, discarding a . Drawing the would be nice, though.
Potential hand worth:
* Lowest: tanyao (silent), 1 dora = 30 fu 2 han on discard 2000 pts
* Riichi & Tsumo: tanyao, pinfu, tsumo, riichi, dora = 5 fan, mangan
* We get lucky: tanyao, pinfu, tsumo, riichi, dora, iipeikou, shan skoku dojun = 8 fan Baiman

(If this were a drama, I suppose sanbaiman was possible, adding in ippasu, an ura dora, and another akidora. Maybe some else would foolishly kan, giving a kan dora and haitei for that last minute drama for a yakuman. This is getting into star alignment terriory, though.)

Edit: fixed yaku name: San Shoku Dojun, NOT San Shoku Dokou -- thanks referee!

The player across from you is somewhat dangerous with that meld of North (which is both dora and his own wind). However, I don't think you want to be worried about defending against that this early in the game. The only absolutely safe tile you have against him is the 4d. The 7b and the suit of dots in general appear to be safe as well, but against a person who already has a freebie yaku and some called dora, the uncommon waits tend to become less uncommon so I wouldn't trust discard reading too much here.

Furthermore, you're looking at a pretty sizable hand yourself. If you drop the 3b now, then pick up a 7b and drop the 2b, you're tenpai for at least a 4 han hand and maybe more if you hit any of the luck-based yaku (and maybe even more if you are able to walk the [456] in dots up to [567]). Besides the 7b, you could also go into tenpai by picking up a 5c, 6c, 7c, 8c, 4b, 5b, 6b, or 8b. There are still lots of copies of all these tiles, and all of them will leave you with at least tanyao, so you don't have to declare riichi to go out if you don't want to. Speaking of which, if open tanyao is allowed this game, I would definitely shoot for that after dropping the 3b, to try to deny the player opposite me from capitalizing on his dora tiles.

I completely missed getting a pair in the characters, good catch!

3sou. Now you have 55667 so you might make iipeikou or the 456 sequence, and you can make tanyao (keeping 3sou would, in addition to making other things more difficult, make a sequence 123 which is not tanyao), akadora, possibly riichi, you might get 5man or 8man for sequence and then discard 2sou to make that the pair and have pinfu, or pick up the 6man or 7man for a pair of that and discard the other one of that so that you have three of 2sou, which is not pinfu but is still tanyao and is still a possibility of winning.

What's been said, mostly. But you mean Sanshoku Doujun, Shanshoku Doukou is a different thing (note the matching ending with "Suu Ankou").

Definitely 3sou. It is the only tile in the hand that can't do me any good. In this position (long way from the lead and close to last) I'll play it slow and wait for sanshoku.

Referee wrote:What's been said, mostly. But you mean Sanshoku Doujun, Shanshoku Doukou is a different thing (note the matching ending with "Suu Ankou").

That was my copy & paste fail. Thanks!