Nah reviving Aeris would be great. Yes it's all very sad and etc. but you just have to make it really hard to do. Then whilst newbies and die hard fans alike can experience the true original meaning, the people who actually care about the characters can be happy as long as they realise that it comes at a cost.
By reviving her I don't mean by collecting a hundred tissues, it'd have to be some really important side quest to like the Promised Land, or something really deep. Nothing cheap or cheesy.
Aeris' survival could have huge implications too, which could again talk about things coming for a price. The new technology available could allow for this. The way I see it you could have three endings.

1) The original, noone really knows what happened to mankind.

2) You save Aeris, but to do so you take the easiest and least responsible path. This leads to events that prevent the final summoning of Holy. Everyone dies.

3) You give up the chance to save Aeris to save the world, but possibly the planet returns Aeris to you afterwards for your true spirit or something like that. Holy is summoned and Aeris lives.

Plenty of deep meanings and stuff possible there, happiness doesn't have to be cheesy.