**Tl;dr available at the bottom.**
I would argue that the Utility Tree is in need of rework, especially with preseason 5 starting in a few months. It's filled with obvious point sinks that don't do much, making it feel as though there are only 1 or 2 possible paths without intentionally handicapping yourself.
The tree also failed to provide for those it was supposed to help. Utility mages and Utility tanks don't really get any specific reasons to go into the utility you wouldn't want on your standard run-of-the-mill champion. Supports, who rely on the tree the most, rarely go 21 points into the tree anymore. I'd be perfectly alright with this if we're talking about tank supports, but when Morgana and Nami have to spend 15 points in defense simply because the defense tree is that much better, you know there's a problem.
Here are some of the problems with the current tree:
**Masteries that no one really asked for:**
-*Scout (increases cast range of trinkets by 15%)*
Even though it's only 1 point, it's pretty useless. The description is pretty poorly worded as well, does it increase the range you can use the red trinket or the range that the red trinket sweeps? Most people will probably guess correctly, but some might get the wrong idea of what it does.
-*Strength of Spirit (Gain 1 health regeneration per 5 seconds for every 300 maximum mana)*
It's weak, it doesn't really synergize with anybody except maybe Singed and it's really awkward for a mana tank to get as they need 3 points in a previous mastery and 4 points in utility overall
**Masteries that are awkward to use:**
-*Vampirism (Grants 1 / 2 / 3% life steal and spell vamp.)*
The stats are really awkward because no one except for maybe Akali can make good use of both life steal and spell vamp. Even if a lot of champs could, this mastery requires way too much commitment to the utility tree for a champion most likely based on dealing a lot of damage. If this mastery was to keep existing, it should be in the offense tree.
-*Expanded Mind (Increases your maximum mana by 2 / 3.5 / 5%.)*
This has a plethora of weird problems. First, a mastery that works best on mages shouldn't be stuffed way up into the utility tree where most mages can't actually get it. Second, this mastery doesn't help with early game mana problems, and late-game almost no one has mana problems. Third, there's little point in putting a late-game mana mastery when the only class that goes that far into the utility tree has tons of mana regeneration options already. Finally, supports can't really benefit from this at all considering most supports have any mana scaling items or abilities (except for Soraka's Infuse.)
-*Intelligence (Grants 2 / 3.5 / 5% cooldown reduction and reduces the cooldown of activated items by 4 / 7 / 10%.)*
The active item reduction can be useful, but since there's no other choice to fill your points on the same tier, it means builds that have less active items don't get much out of this mastery. The reason I say that is that cooldown reduction is extremely easy for supports to get even without masteries. Even with the upcoming Talisman CDR nerf (which is pretty well deserved) I can still max out my CDR with only 3 or 4 items.
**Masteries that are way too weak:**
-*Bandit (Melee: Champion kills and assists grant 15 bonus gold. Ranged: You gain 3 gold each time you attack an enemy champion. This effect cannot trigger on the same champion more than once every 5 seconds.)*
The melee bonus is somewhat decent at least, but the ranged bonus is nearly useless for such a high tier master. How many times are you going to go up and AA someone as a low damage champion who should be spamming their spells during fights? If this was intended for laning phase, then how many times are you going to go up and AA your opponents in a lane in which one of them can lock you down for 3 days if you step a bit too far forward and the other is better at autoattacking than any other class in the game?
-*Inspiration (Grants 5 / 10 experience for every 10 seconds while near an allied champion with a higher level.)*
The idea behind this mastery is great, but the numbers are far too low. Even going from level 9 to level 10 requires 1080 seconds of standing beside someone, and that's considering you put a full 2 points into this.
The utility tree needs to be reworked, most likely in a major way. There are a few good masteries in here that reward active play and allow for customization, but they are overshadowed by the amount of useless points you have to burn if you want to get a full 21 points into this tree. At the top levels of play, few pros still go 21 points into utility, and that's usually only with champs that have almost no way of getting any mileage out of the defense tree (a hard sell considering how universal a lot of the defense masteries are.)
**Tl;dr:** Mastery tree has some good ideas, but way too many mastery points are wasted. Some masteries are too weak, others are put in the wrong tier or tree and some simply shouldn't exist because they are useless to 99% of the champions in this game.