I would play with my friends, we're old epic fans.
I also have few ideas to keep players for long time:
1) pets from newer epics and staging - staged pets aren't op, pets won't lose on their worth, there will be a need for them whole time. Also it will bring economy on server.
In e5 you have only a few pets, after few months server will get flooded with kentas and angels, they will lose on worth and become common. Noone wants that, so newer epic pets and staging will prevent from that.
2) all r7 belts could have 2 slots - that's not op imo, but it helps to highlight the way you build your character (dmg warrior, tank warrior or mix of both etc)
3) adding tier 2 and tier 3 equipment with bonuses on each piece:
tier 2:
-helmet +15 p acc/m acc
-gloves +5% cast/atk spd
-boots +5% mov spd
-armors: 1) warrior +5% p def, +5% max hp; 2) hunter +5% evasion, +5% atk spd; 3) magician +5% int, +5% m def; 4) summoner +3% int/str, +3% p/m def
-weapons 1) one-handed +3% atk spd (including xbow but with 6%, since it's 2h); 2) two-handed 6% p atk (m atk on staff ofc)
tier 3 same, but a little increased, let's say by ~50%, so +7/8% instead of 5% on gloves etc, that's not huge difference
It doesn't make that stuff op, but let you feel a little difference. Also it's only on t2 and t3 gear. It's hard to hit 150, but 155 and 160? It's insanely hard. So these bonuses are proper reward for all your hard work and once again - they don't make you op.
In e5 there's nothing to do when you hit 150, so adding 155 and 160 gear will encourage player to reach these levels, it's hard and takes a lot of time so it will keep them busy for **** long time.
5) new dungeons with stronger mobs (sort of hc) and extremely hard bosses which drop legendary weapons, armors, rings
-legendary weapons and armors, just like regular but have additional +50 random stat (str, vit, int, wis, dex or agi) - just 1 stat ofc
-legendary rings - normal r7 rings add +40 to 1 stat, legendary would add 60 or 80
It would take a lot of time and trouble to get your weapons and armors with right stat, since you can loot a 2h axe with int or wis stats - that's useless, so you have to keep faring to get the right one