Reachmahjong.com

There's two main ways to complete this:
-scout a taatsu from the pinzu dora or the 4m and riichi
-pon the haku and get a pair from somewhere else

The 2333p ryantan looks good for the second one at a glance, but actually waits for the same amount of tiles as 3335p. You have to pick one wait in tenpai anyways, and drawing 12p now leaves you with a bad wait. For making taatsu the 2p is terrible.

Although it is the dora and this hand isn't completely developed yet, keeping closer tiles gives more flexibility when chasing tenpai. I'd rather just get rid of it now before it can become dangerous later (on the off chance that it doesn't develop).

Kill it now. Kill it with fire. Sucks that it's an isolated 8-pin dora, but it has to go or else it may become more of a liability, rather than a benefit. Plus, there's already two red dora in the hand fitting rather nicely, so losing 1 dora can be affordable.

As an alternative, scrap the 4-man, if the intent is to cling to the dora.

It's dora, but its isolated. So is the 4man isolated, but its a tad safer than is the dora, so I'll drop the more dangerous of the two first. The longer you hold it, the more dangerous it becomes.