Played Eve on and off for ten years. I usually play until I burn out. Null space is fun, but eventually attention wanders.
I'd like some things to be similar to EVE, though;
Politics!
The ability to be an utter scumbag. Being a scumbag in a game is not the same as being a scumbag on a forum or in real life. I loved scamming, and being scammed, in EVE. If was something that kept your mind alive while you snored through the flight mechanics. Scamming should definitely be a thing in ED. Not code exploits, but law exploits. That's quite a big difference.
If anything, the option to be able to go solo should really take the gloves off in multiplayer. Don't like the rough stuff, play solo. EVE can be exhausing because there is no break from it.
Manufacturing etc
The game will be very stale for late game if you have grinded for the biggest meanest ships and most combat becomes very easy kills. You need late game activity branches (form your own mercenary fleet, start making ships, industrial scale mining. Naturally, dogfighting should remain the central focus, but it's likely to get dull if that's all you can do.
I'd not allow any of this in Solo or Small group mode, btw. Where would be the risk?