I agree, and would actually argue that the tier 3 runes could be pushed up in power just a bit as well. For tier one however, I agree that Font of Life is the worst of the bunch, and I use it only if I absolutely have to. I was thinking what might replace it, and came up with a few ideas:
Vitality/Font of Life
Nearby allies gain bonus health regeneration equal to 2+.08% of your maximum health (every 5 seconds). If there are no allied champions nearby, instead gain 10% tenacity.
The idea is to preserve the team-oriented healing effect, but making it not as terrible, and opening up more options for non-support tanks.
Adaptation
Getting hit by an enemy champion's ability permanently increases your armor or magic resistance by 2, based on which would prevent more damage from that champion, up to a maximum of 20 points between the two. [Alternatively, increase both by 1 each time, up to a max of 10 times.] After reaching the cap, either getting cc'd or just getting hit with an enemy ability will either deal some damage back in a thornmail-esque kind of way, or could reduce your abilities cooldowns by a small percentage. Adaption has a 20s cooldown for the first part, none for the second.
An idea based off of manaflow band, but for those looking to get tankier!
Final idea: Just move some of the ward utility runes out of the assassination tree and into this slot, but ditch the 'extra damage' parts and just focus on increasing their utility. There's no reason those runes should be over there, save maybe eyeball collection.
Or, just got this crazy idea: instead of just focusing on the damage classes, where assassins and ADC's have objectively more rune choices than anyone else, just add a fourth choice here and there to the Resolve tree.
