And by allowing players to use their full capstone kits, that may just exacerbate the problem.
Sure in theory, DPS roles may be the easiest to 'balance', albeit with a lot of rework considering stuffs like potency creep and such. But how will they balance the other, especially tanks & healers? Since you mentioned DRK I'll use that as one of the example and few other:
- DRK's [The Blackest Night] -- how will they balance this ability to lower content...say, Sastasha?
- Tanks invulnerability cooldowns and their self preservation abilities.
- Healers healing potencies and their plethora of instants & abilities? WHMs will be the most noticeable due to the fact having CNJ as a the first potential healer class at the start of game, and their pre-50 kits vs lv50+ kits.
- Several classes' buffs such as DNC's [Devilment], DRG's [Battle Litany], BRD's [Battle Voice], etc.
Additionally, while I can understand how you come up with the idea that newcomers that may be encouraged, there's also the other side of coin of this. How do you know---or should I say: ensure that these newcomers will be encouraged instead of being disappointed of not having access to those flashy skills yet? Because there are certainly portion of players that do not enjoy getting 'carried' all the way through their gameplay, they exist. Considering how SE is trying so hard to not let any kind of 'meta class' emerging nor imbalance occurring, it feels like implementing this new system would be the last thing they would like to do.
I don't fancy getting my arsenal of skills greyed out...but to avoid that I just avoid queueing into lower duties and roulettes when I don't want to.