you definitely should start at the front!!
You are one of those people?? ;) It's been so long since I've done a road race that I forgot.
'Round these parts, 8:00/mile gets you top 5%, worst case top 10%. I think I did 7:30 ish pace at a not-quite-10K and finished like 20/1500. Lining up anything beyond 50th is just a nightmare of "hey, we can run abreast!" and "whoops wrong playlist lets fix that" and "let's stop and chat!" and kids flaming out after 100 m.