I'm still on a mission to work this out for myself...
I think from what I've seen and read, these are some of the differences;
- neck angle relative to body
- headstock break angle
- the way in which the mahogany wings of the body are glued to the neckthrough construction (Gibson uses a V shaped glue technique)
- pots and input jack (easily replaced)
- wood quality (obviously cheaper species of mahogany on the epi)
- finish (poly vs nitro)
- and the ones you mentioned
If the neck and body angles are different, then they're subtle enough for me not to notice. In what ways would you say they differ?
Both use the v-shaped glue technique for the wings.
Differences I've noticed:
- The Gibson has a nitro finish, whereas the Epi is shot with poly.
- The Epi has what looks to me like more of a '60s pickup orientation, as they're closer to the bridge.
- The neck heel area on the Epi is more squared off, whereas the Gibson is more rounded.
- The Gibson has a slightly more angular body shape, whereas the Epi is slightly more rounded.
- The Epi has somewhat improved upper fret access.
- The Gibson has a little nub on the bottom of the headstock detail.
- The Epi's tuners and bridge are Epiphone hardware, whereas the Gibson uses Grovers etc.