Right now it is common to use a 5 piece set and possibly a monster helm+shoulder combo but then the rest are stat just boosts seems like a waste to me. The concept: add 5 piece sets that are designed specifically to synergize with a specific set, monster sets included and are the basis of this idea.

Examples
deadroth armor (unique appearance) : Add stamina health and weapon damage 5piece set boosts melee damage by 5% and if the maw of the inferno set is equipped your light attacks become fast melee claw attacks that deal X additional damage and possibly bleed damage(scales with stamina and WD) and your heavy attacks become a fire cone that deals flame damage but costs magicka but still scales of WD but you are unable to use weapon abilities and the passives for weapons will be weakened. (Overload can still be used and it will taki priority over this set) If maw of the infernal set procs summons 2 deadroth.

Titan armor (unique appearance): adds healing received done and max magicka 5piece set: DOT moves deal 7% more damage and if wearing the nightflame set DOTs have a 6% chance to leave white fire that burns enemies for X fire damage per second for 10 seconds(does not proc itself) and the nightflames proc chance is increased by 2% and the range is greatly increased however non DOT moves are 12% weaker.

Willows symbol (crafted): adds regen 5 piece reduce resource consumption by 5% if wearing exactly 3 pieces of willows path gear you gain spell and weapon damage equal to 15% of the associated regeneration and add armor equal to 3 times your health regen.

What do you guys think sound interesting enough to expand upon?