The descriptions for skill levels apparently fail to mention everything that you actually gain. Some skills gain a shorter recharge time when you level them, even if it doesn't say so. Tank charge is one of them. The assassin's cloak skill only says that level 2 makes it drain slower, and level 3 lets it recharge while you stand still cloaked. Really, one of the best effects of leveling is that the cloak engages faster. At level 3, it's instant, which can really save your *** against turrets. Also at level 3, it makes your first few hits crits as you leave the cloak. Anyone know of any other skills with undocumented effects when leveled?
Pretty sure that's the same for most, if not all, classes/abilities. For the support, the Turret, and Hack most certainly go faster, i'm not sure about airstrikes, but I don't think they do. With the Gunner, Slam and Grapple(the ability) come back much faster at level 3.