The final thing I want to bring up is the trees because not all trees are built equally either. Some of them are very powerful and very reliable and others really need some help. We'll go from left to right with them starting with Martial.
Martial is a very solid power to pull from, it's basically required if you're running a melee build or really anything but a pure will build. Unfortunately due to the nature of the game, Vitality and Focus are really the only two things that are worth taking from it; though those two abilities alone justify taking the power. Focus makes you faster and you attack more often on top of that though the attacks themselves don't deal much damage, both things you want if you're going into melee; you also supposedly get more hit dice though if that is true it doesn't show up on your character sheet. Vitality is the best end of combat heal in the game and the best armor ability in the game. The others are situational and not as good as you think. Pugilist feels like it needs just more power and possibly a decrease in the cost, its weakness comes from the fact that weapon effects can be powerful beyond the damage they can do. Guard relies on you getting hit and the damage you deal in response though a good damage type just isn't high enough to justify keying off of armor and block, especially with a character that probably doesn't have much health or strength to begin with. Alacrity is good but it relies on an rng based defense for a character that would probably be better off just attacking more rather than rolling the dice on dodge, I don't think the dodge bonus actually works though because the numbers don't increase and even when I take it a lot I don't see a difference.
Fire, it has the most powers out of any of the trees and so many of them are summoning powers. Ironically fire is probably one of the worst powers you can take if you are a summoner in my experience as a lot of what it does has friendly fire problems and even with high fire resistance you'll be frying your own minions pretty quick.
-Pyromancy is a trap, only will characters will want it but it will kill your minions.
-Burning heart is a rather disappointing heal though I suppose it could work for a dex build if there wasn't already a better element for a dex build. The real strength of this power comes when you get immolation.
-Inflame is a great way for a will character to increase their accuracy, something will characters desperately need. The ifrits are nice but suffer from the same problem summoning with fire does
-Immolation can be good on a strength build though it only really shines when you have burning heart and can apply a lot of scorch really fast. Combine the two and you can see some truly terrifying damage numbers come out.
-Shamshar feels bad. It's a worse version of skera in a number of ways. You're basically stuck playing a dex build with this and even then it's going to be a sword and shield murabizun which isn't the best option there. I honestly think this would function better if it gave you bonuses if your encumbrance was higher on account of the fact that the best blunt and slash weapons are all usually heavy enough to put you close to the limit on this tried running a fire lightning mubarizun and it was a nightmare to get running and was worthless against the beetles that show up early in the game and once again the bonus hit dice didn't show up in the character sheet. To expensive and weaker than a similar option.
-Flame cultists are really cool for that deal fire in a line nonsense they have when any summoning happens but once again you'll kill all of your summons doing that. Can make for a decently fun summoner early game but gets hard stopped by anything with a lick of fire resistance. The damage they pump out and the damage the fire lines do is paltry for the price though, there are better summoning options.
Lightning is a star player in the powers, it's the go to if you are playing a dex character and that's it but what it does it does well. Sadly it really only does one thing well which is Skera.
-Electrokinesis is a trap, any character that's going to want to use it is a will character and will have summons for defense. This will kill your summons pretty fast actually.
-Electromancy is a summoning ability and the ability to pray enemies to death, could be a fun way to run a zealot but you run into the problem if you run out of prayers and everything isn't dead because your summons probably will be.
-Power Charge suffers from being a low damage increase, there are better ways to pump your damage. Might function well on a dex speed character that can really pump up their charge level but Skera exists and it's really powerful.
-Skera the premier ability of the lightning Tree. An incredible pick, expensive but worth it. The damage increase is sizable the speed increase is always nice. If you're playing a dex build there is really no reason not to take this. You should in fact be trying to get this by the green tower if you can.
(will post the rest at a later date, I have stuff to say about all the elements but life is coming up)