Make sure you can Automatic Quicken every spell level you have access to, and get piles of Multispell feats. More spells per round means you can counterspell like mad and still get to do things - that's perhaps your best way of dealing with Epic spells. In that vein, pick up Epic Counterspell as one of your Epic spells, that'll help prevent much of the cheese your opponents will try and send in your direction.