Your low WtSD and high AFs tell me you don't call enough when it's likely you're good.
Things like peeling a street or two with stuff like 88 on K73r for example. Against maniacs, which you should be searching for, it's very important that you're capable of calling them down with marginal hands or else they'll run you over. Obviously you can play ABC, wait for a big hand and hope to stack them but big winrates will come from actively hand reading and trying to exploit them.
You could up your steal % as well, particularly from the SB.
I don't think light 3betting would be hugely important at 25nl but doing it a little more frequently in position couldn't hurt. Opponent tendencies are very important here.
Against tight regulars who are unlikely to call you, and especially when they're OOP, it's important to use a polarized range of hands you're happy to stack off with (like QQ+/AK for example) and stuff like SCs/suited two gappers/suited aces which you can't coldcall profitably but will play well postflop those rare times that you do get called. If you get 4bet you're happy to fold as you haven't lost anything. However, if you 3bet a hand like 99-JJ or AQ and get 4bet you'll have to fold and that cost you the opportunity cost of coldcalling.
Against bad regs or aggressive fish who'll call too much even when OOP it's fine to have a non polarized range. You can have an extremely wide range in these types of situations, it's almost like an isolation raise, and expect to take it down with a cbet on the flop very frequently.
W$WSF would be handy.
Have you read all the threads in the stickies?
Micro Stakes Sticky
Small Stakes Sticky
Small/Micro Stakes Video Collection
Anthology
Have you considered getting a subscription to a training site, DC is pretty cheap?