Well, I think I would either take the Biscuit and Victory out, or take the Amber malt out. I think they are all too similar to have all three in there, and it would have an overwhelming biscuit taste. I would just pick one of those, and keep it under 10% of the grist. I am a big fan of all of those malts, and have made a beer with Biscuit and Amber, and it was a bit much for me. I just bottled a beer that was base malt and about 12% Amber malt, and the Amber gives the beer a very strong finish. I like it, but the point of that beer was to have the Amber malt dominate.
Other than that, I would simplify the hopping schedule (the varieties are all really good in an ESB though). For my ESBs, I like a schedule of 60, 15, 5 (dry hops are good as well). This seems to give me a really balanced dram, which is how I like my ESBs.
Hope that helps,