Do you agree with those ballpark numbers, and if so would it actually make those items more fun? Also bear in mind that an activated item would swap item slots and be made into a trinket, so the issue with few gauntlets being used would be further exacerbated.
Yep your numbers are about right I think, I don't know for sure if it would be more fun, since that's a kinda arbitrary measurement, but I think I'd enjoy a bit more stuff to do in combat short of rmb everywhere and activate skills every 5 seconds or so. Maybe I'd just like a little more micro reward.
Some gloves can go in the activatable slot, some can go in the equip slot, the choice is more what to spend on than how to make use of slots in the critical part of the game (early-mid) and at the moment the only smart choice is to stack HP for about half the characters. Artifacts aren't obvious in which slot they go in from their picture, and neither are the trinkets. Theres no need to restrict trinkets to the only class of item that can be activated apart from consumables.
I didn't mean to have 100% proc chances on slows permanently, as you say the effect would be small and then its just back to being a crap item for the most part (I think few players would rate maim to be equal to something like motb).
I think it at least open the door for something other than health stacking in a coordinated match...being able to focus fire and snare/weaken/stun/silence/mana drain a single target is exactly the kind of move that will counter health stacking, since a team of three can buy one of each of these activatables and properly disable an enemy to the point where having 4-5k hp isn't going to be enough on its own to prevent a ganking.
The artifacts are all great examples of this, if we had instead of the wyrmskin gloves, the journeyman's treads and the duelist's cuirass cut down versions of the bracelet of rage, deathbringer and the Orb of Veiled Storms, I think there would be a lot more thought into whether you actually want your entire team buying +hp items or not.
I've tried playing Sedna as a support character, and it's definately weaker than just HP stacking like normal. Taking the cloak of night and trying to get ninja pounce/silence combos going, while spending nearly all gold on buying items for an UB ally and getting cit ups just isn't effective. With a bunch of activatables that option might be there, which would make things more interesting and give players more options than "Stack HP and spam skills".
I realise this means you'd need to be able to buy skills that some characters get, which changes the skill pool by allowing everyone to get a blink/silence/whatever ability. The advantage is that you get a more varied fight, open up a whole bunch of new strategies (metagame) and allow some team-play options that just aren't there at the moment. Yes if you give everyone the ability to 2sec silence a single target with a 5k item that means Sedna is no longer unique, but the difference is that she can do it every 10 seconds, whereas an item would have a nasty long cooldown (30 - 45sec) so you could only use it as a surprise attack in the important 3v3 engagements rather than just spamming it like people do with pounce/silence/spit/towers/bite.
Slight tangent here, but just pointing out: the argument was not "introduced" in DoW2. Someone took it and applied it to DoW2, buts its been used in much older games, the oldest of which I know of are Warcraft 3 and Guild Wars, but probably in ones even older than that, as well.
My argument is in no way water tight, I don't pretend for a moment that this would magically improve the game for free. It would need serious balancing thought and would take some implementation time (though it wouldn't be much...you could do it all in a lua mod) that just doesn't appear to be available at the moment.
But I do think it would be a better game with more activatables.
Bleh wall of text.