Problem here (at least between a and b) is that it's very much a matter of taste. Some people like style a) and some people like style b). If I changed everything to style b) (which would not be difficult at this point), there would be a shitstorm over on GD. And, frankly, they might have a point, whereas I ignored the complaints about switching shower/summons. Collapsing the shower and summons down into a combobox reduced the vertical height of daily deeds. Collapsing the others would not, and would just add clicks.
So, I won't say "no" to that one, but I'd need to conclusively see that more people would prefer b) over a). Heck, I might prefer a) myself.
Addressing c): the only time I've seen the skate deeds are when I hacked the source code to always display them. I've never done the sea to completion. When I mentioned "hey, should I give the combobox treatment to skate deeds?" over in the DD discussion thread, I was met with crickets; I think the user base of that particular deed is rather small.
That's not a "no," that's just a "that is very low priority for me."