So talents in PoE are mostly pretty lame, right now. With a small number of significant exceptions have your basic boring-but-good talents (ex. Two-Handed Style, Weapon Focus), your interesting-but-bad talents (ex. Brilliant Radiance, Ancient Memory), and why-would-I-ever-take-this talents (ex. Field Triage, Unstoppable). I think this is a regrettable state of affairs, and I wish it were different, so I thought we (the board) could come up with some examples of talents that we think would be interesting, or of fixes for existing talents.
I'll start - this is not a super-exciting example, I'll admit, but I think it could be interesting.
Demanding Presence - As long as you engage an enemy, they can't make disengagement attacks against your allies. In addition, whenever you and an ally have both engaged an enemy, that enemy is flanked, regardless of your positioning.