The upgrade trees will be ranked out of a possible 4 points (1 point per valuable upgrade in a tree) and will sometimes include .5 points for upgrades that can be good/are niche. (The upgrades are rated in the same order they are shown in the picture).
Electro Mage (3.5/4) Electro mage & Electro mastery are both excellent skills and the main source of damage for elemental builds. Electro bug & Energized aren’t great but are required to unlock Electro mastery. I gave them each .5 points. The last .5 actually comes from the fact that Electro mastery is used to unlock the excellent overload synergy.
Quick hands (2.5/4) This tree is mediocre. Quick hands and Fresh clip actually give a damage increase which makes them valuable. But Kill clip and Armed and ready are mostly useless. Fresh clip does allow the Mini clip synergy to be unlocked and Mini clip is one of, if not THE, best synergy in the game.
Frost mage (4/4) Freezing enemies is excellent and dealing %Hp damage with frostbite and shatter means that it scales at any darkness level. The weakest upgrade has to be ice shard as it mostly works with low ammo guns/Mini clip. The synergy this tree unlocks is pretty bad however which prevents it from going to 4.5.
Haste (3.5/4) This tree is required for most non-summon, non-Miniclip builds because run and gun let’s you move while shooting. As we have discussed multiple times at this point movement is excellent in 20 minutes till dawn. The only skill that isn’t as good is blazing speed, mostly because burn is baseline not very good. In the wind may seem a bit bullet damage centric (and it is) but 40% movement speed is nothing to scoff at.
Ghost friend (3.5/4) The ghost friend itself and the Vengeful ghost upgrade are sub-par upgrades. But summon attack speed is extremely important which means the Energetic friends and In sync upgrades are absolutely mandatory for a summoner. The last .5 comes Vengeful ghost unlocking the Summon Mastery synergy, which, wouldn’t you know it, adds even more summon attack speed.
Light weaponry (2.5) This upgrade tree is a bit odd as it relies on your bullet damage to increase your summon damage, which means it mostly/only works with the grenade launcher, crossbow or revolver. The two dagger upgrades themselves are fine but a little unreliable and got .5 each. The Sharpen upgrade is pretty terrible, but there is no reason not to take it when you are playing a summoner build. The best upgrade in the tree is actually heavy weaponry simply because it is the only source of consistent and controllable damage. The last .5 is once again earned because the Dual wield upgrade grants access to the Summon mastery synergy.
Magnetism (2/4) Pick up range isn’t a very important stat. Even less so when you focus on mobility. But if you wave nothing else to take I usually recommend taking Magnetism just for the quality of life.
Holy shield (3/4) Holy shield is the best defensive upgrade tree in the game, and the fact that divine blessing increases movement speed and stalwart shield makes the shield reduces its cooldown only makes it better. The only outlier here is Divine wrath which is mostly useless.
Dragon egg (3) The dragon is the strongest summon on its own as it can be played with any build. The Trained dragon upgrade is excellent and I recommend picking it over almost anything else. On the other hand Aged dragon is just okay even though it works with Dragon bond. But Dragon bond only works for bullet damage builds and you would prefer having the scythe and daggers in a bullet damage build every time. If you somehow managed to unlock the dragon and the Aged dragon upgrades at 19:00 the Dragon bond would only be granting you an 11 bullet damage bonus by the 5:00 point which is the last time damage ends up mattering. Which is fine, but usually not worth taking over most other upgrades unless you are trying to build a low base damage gun into a gun damage build (i.e. Magic bow or Batgun)
Vitality (1/4) This defensive tree is mediocre. Most of the time it is much better to just not get hit. Both HP increase upgrade get a .5 because they at least can be helpful for the last few minutes of a game in making sure you survive. Anger point however only works on Diamond and is just OK even then. And regeneration is a bit too slow.
Magic lens (.5/4) The only useful-ish upgrade is the first one. But even so it is only ok on bullet damage or summon builds. I would pick it over some upgrades in those two builds but I generally recommend avoiding it.
Double shot (4/4) More bullets are good for almost every build, with only summoner builds not really needing it. Fan fire is a great upgrade that increases your survivability as your bullets knock enemies away when you reload. The worst upgrade in the tree is Split fire which only got .5 simply because shooting backwards is a bit unreliable. The last .5 points is actually awarded to Fan fire because it unlocks Mini clip.
Rapid fire (2.5/4) Fire rate is a useful stat for most builds, but it is also not that hard to obtain as most guns have a pretty good base fire rate. Rapid fire, Rubber bullets and Light bullets each give fire rate which allows them a score of .5. But siege is completely useless as not consuming ammo isn’t useful, and standing still to do it is even worst. The additional point then comes from synergies unlocked by this tree. Siege unlocks Stand your ground which adds projectiles , and the other .5 points is awarded because the tree is required in 2 other synergies, although those synergies are entirely bullet-damage specific.
Power shot (4) This tree basically IS the gun damage build. Splinter, Big shot and Reaper rounds give you area damage which is very useful. Power shot itself however is a bit weak and the additional knock back is mostly annoying as it pushes your XP away so it only gets a score of .5. The last .5 is awarded because Reaper rounds unlocks the Death round synergy which is pretty much mandatory for bullet-damage builds.
Take aim (2.5/4) This tree is a bit niche. Take aim, Penetration and Sniper are mostly useful for their bullet speed. However bullet speed is only useful on the grenade launcher and the shotgun. The Assassin upgrade is actually quite good as % based damage is always useful and is the reason it deserves a full point. It is also one of the few ways to make the flame cannon viable.
Glare (0/4) This tree is almost entirely useless. The damage and its frequency are mediocre. The only use one can get out of this tree is in combination with the close combat rune when playing a summoner build. The close combat rune increases damage dealt to enemies within vision range and every upgrade in the tree increases vision range.
Pyro mage (2.5) The Pyro tree is the worst of the elemental upgrade trees. Pyro mage itself makes your bullets inflict burn, but burn is a slow damaging condition. In a game all about surviving a short period of time something as slow as burn is pretty bad. For the same reason Intense burn (which increases burn damage) is pretty bad. Soothing warmth is a good survival upgrade when paired with the dragon or most elemental builds and is excellent/mandatory on Diamond. Last but not least Fire starter is excellent. It adds a lot of damage to any build and unlocks the Overload synergy for an additional .5.