What is main problems in PVP? Right, abusers of broken combo of various characters. Even sanbaggers and minmaxers make a treat to fair players in first with that and only second with big difference in power level.
So devs no need nerf or buffs for bring back old fun times. They need destroyed curent meta ties. Mandrake/Flatline, Flatline/Ifrit, etc.
Do you play in HOMM series? III? V? In HOMM if you put best creatures from various castles in one combo you quickly find what they start often skip turn and miss in battle. Some castles neutral to ech other, but some is blood enemies. So put Archangels with Archdemons in one party is bad idea. Especially when you also use Behemoths and Gydras. How about make our analog of morale/dismorale system based on factions? Even lore of Hero Hunters say about it.
For example, look most standart combo. Dogface, Flatline, Mandrake, Butter, Ifrit. This is five completely different main ideas.
Info screen of Rangers factions say what everyone scare of them, info screen of Magistrate say what this peoples is heavy weaponry current peacemakers and love rules & law, Morlocks instead is pure anarchy, Patriots wanna back old World Order before Z day, UAF is military of currrent World Order.
So Dogface never work together with Mandrake, unwelcome to Flatline, kill the Ifrit and only Butter is his true ally. Same boat and with other.
Make big penalties for parties with various factions and make great buffs if player use one faction or few friendly faction. Neutral faction is no bonus. With this system all players force to find, learn and play with all roster instead current top 10 chars.
Another proposition – lock some heroes for main PVP faction tournament. Again all this based on faction. If we have tournaments with faction of mounth – lock their enemies.