Can't really disagree with debuff spam being an issue for more melee-oriented characters. Received damage is also a thing, but I guess we'll wait and see how they feel about the current tweaks in Ambuscade before applying them globally.

Otherwise, there are a few things that could happen...

Mob End:
- Diminish the accuracy of a debuff based on the potential number of targets it would hit.
- Add cooldowns to select TP moves so they can't be used in rapid succession.
- Revisit Subtle Blow and/or melee TP feed.

Player End:
- Make all status cures AoE by default.
- When cured of a debuff, gain a temporary resistance to its effect that diminishes over time.
- Improve the effect of elemental and status resistances.
- Holy Waters always remove doom/curse/zombie.
- Remedies adjusted to remove everything and possibly stack to 99.
- Add more resistance friendly gear or a means to augment existing items without sacrificing current values.
- Add more ways to better control a mob's TP gain (ex: Plague) and hinder their potency/ready time (Addle for TP moves).

Otherwise, some of the other factors to the anti-melee status was the bonkers evasion of high level content and the general trivialization of BRD and COR in the wake of GEO. Tweaking evasion ratings like they did with this patch is a step in the right direction, but I'd argue the content isn't terribly entry level friendly with the earlier phases of progression largely being "done" by other vets with little incentive to backtrack. Of course, this segues into how solo friendly things should be, which not everyone is keen on.