Note that Epic past life benefits work in heroics. Earning much faster reaper xp at Cap before your reincarnate will help you in heroics. Epic past lives go much faster than heroics, especially if you willing to use Major Slayer pots; xp pots obviously help too but nothing beats a Major Slayer Pot x3 progression rate. Definitely figure out which quest end chests have tokens of the twelve and farm 20 while you level epics. Never waste money buying True Hearts of Wood or Hearts of Blood, just a plain bad return on DDO points. If you reach level 30 you definitely want to get the benefit by doing an Epic Reincarnation before you do a heroic reincarnation. After you do an Epic Reincarnation, you can level up to 30 again and do another one, but slayers and quest completions are not reset when you ETR so it gets harder to level up epics after each reincarnation.