Good question

X13 is the obvious first step.  I'm in the zone with adding the new algorithms, and X13 shouldn't be much work to add from X11.  I'm out of town this weekend, so it probably won't be finished until next week, but should be pretty quick.

After that, like you said, combining payouts has been a major request, and shouldn't be much work.  It should have been done by now, but I like to be extra cautious on things like payouts.  Don't want anything to screw up there

Past that, I like the idea of the algo-switching, but it does require some extra thinking.  The way it is done with NiceHash is really neat (props to them for the idea, and funding the custom version of sgminer), but at this point, the new version of sgminer seems to have some issues.  Ideally by the time I've got the other stuff done, the major kinks will be worked out in the new sgminer version, and we can look into an algo-switching version of WP.  The actual algo-switching part isn't too tough (pretty easy in fact), the bigger issue is figuring out how to do the switching based on user preferences.  For example, if your miner can do 1MHs Scrypt, and 6MHs X11 (normal is 4MHs X11 for a 1MH scrypt), you would need to be treated differently in terms of what is profitable than someone with 1MH/4MH.  There is also the difference of preference of power consumption.  Some people would like to bias their miners towards X11/X13 because of the power savings, some users don't care, and would prefer to mine whatever is the most profitable (regardless of power costs).

Doing algo-switching on a generic level (preset values) is reasonably easy.  Doing algo-switching with user preferences becomes quite a bit more difficult