Medicine, survival and science are others I find very useful.
Speech, however, makes the game dramatically easier (far less running around for stupid crap when you can just talk people into doing what you want).
Funnily I have not taken speech on half my 9+ characters.
One because it was a raider build, the other because I dropped charisma for role and I dislike the whole drop C and tag speech idea that is common now'a days.
The rest just because they were not chatty.
So far I say speech is sooo over rated, a few fights can be avoided with it.
Mostly however it eats up a chunk of fun quest stuff and other bonuses that you miss, just for an XP reward.