depends on what you want your end tone to sound like. i go for the final mixed cd tone live, but many others want to sound of an unmic'd amp. if that's what you are after, then you will need to roll off a bunch of high end and in some cases high mids to get there. the Epsi can be helpful IF you already have an IR that sounds like an unmic'd speaker...which i haven't found. it takes a mic to get the speaker sound, so you are kinda stuck with it.

i made some fizz reduction presets in my superpack that are designed to give more of an amp-in-the-room tone. maybe try some of those and tweak from there?