So I think I've really settled into a fairly potent deck right now. I'm fairly happy with it, except for when I play esper type decks with so much counterspell that I can never get anything on the board. I have Rest in Peace sideboarded in for dredge and flashback type decks. What can I do to counteract Cancel, and Rewind, and Dissipate, etc etc etc etc. That is about the only type of deck that I do get really frustrated with.

http://deckbox.org/sets/319287

Really your options are limited.

First off, I'd suggest going with Ash Zealot over Rest in Peace as that can help in more situations than just pure graveyard hate. Let them wipe the board on a flashback, it still pings for three damage. R/W also has access to the two best anti-board wipe spells currently available - Rootborn Defenses and Boros Charm - in this case, the Charm would be much better for you.

More to the point, if counter-magic is an issue, you can only really deal with that via Cavern of Souls, Nevermore and, to a much lesser degree, with Curse of Exhaustion and some clever playing on your end.