I can't tell you about an Epic 6, but I can tell you about a 10 lb, 11 oz Epic 5.
Balance is fine, but it is heavy. I don't have a problem with neck dive, but my knees tell me I've been playing a heavy bass the next day.
I use the Italia 4-inch wide straps. This bass definitely calls for a wide strap.
Neck profile is substantial, but not annoyingly fat. My main bases (or basses) for comparison are my Series I (4-string) some Sadowksy 5's and a Carvin SB5001F. I also had an Essence 6 - the Epic is definitely fatter (deeper and probably wider) than the Essence.
The guys I play with weekly actually request this bass
(a 1995 Walnut Epic 5 Fretless) the few times I reach for something else. And while the filter style tone one my Series I is both unique and powerful, sometimes the Treble+/- and Bass+/- is just exactly the ticket.