

This is a tough one, and I think I could also be happy cutting any of the character tiles here. In an online game with time restrictions, I might have discarded the dora given less time to think about it.
I don't really feel threatened by any of the other players yet, so I'm not too worried about going fast or slow at this point. Ultimately, I choose the 4bam because it allows me flexibility: I get to keep both copies of the dora tile in my hand for now, so if I draw a third copy or someone cuts one, I can bring it into my hand and change the [234] shape into a [333] shape without slowing down, but I'm still only one away from tenpai so if later in the hand I draw a 1/4/7 of dots, I can go straight into tenpai if I feel comfortable discarding the dora then.
This hand has a potential for sanshoku, but I'm not really feeling it. If I go for sanshoku and I have to open the hand to get it, then I only gain 1 han, which only offsets the 1 han I lose by discarding the dora. I can get an extra 2 han if I can make closed sanshoku, but I can also get an extra two han by changing the [234] into a triplet of dora, which isn't required to be closed.