I've been playing FlyFF for about thirteen years and I've played a lot of pirvate servers. I can safely say that Prologic is a pretty decent server, but there's a lot of QoL stuff that could improve it a fair bit.
Vaelish Shop Stuff:
Tickets to vital levelling areas are extremely overpriced, reduce the prices to something we can actually afford!
Frankly everything in this shop is extremely overpriced beyond the penya rate of the server, reduce prices for happier players!
Drop pets: Add an extra tab to buy drop-collector pets!
New NPC shop suggestions:
Green Armour Shop: The server's drop rates are pretty low for this kind of gear and a lot of classes THRIVE on green armour. I know there's the "coupon" shops, but the limiting factor is that we quickly outstrip the ability to change out gear based upon the server's XP rates. The coupon shops also start at 60 so the 15-45 armours are effectively locked off to everyone.
Green Weapon Shop: The server's drop rates vs the XP rates impact us again here, we burn through gear really fast, leaving us without the ability to have vital gear, also the 15-45 gear, vital to certain classes, is again functionally absent because of drop rates.
Sticks (assist/RM/Seraph buffs): make them a one-handed item so they can equip a shield, allowing AoE RMs/Seraphs to tank more effectively and to make levelling stick-based assists less dicey.
Implement tabbed inventory to allow us to hold more stuff during long farming sessions and to make locating stuff less annoying in a busy inventory.
Prevention: Remove the 3min cooldown in non-siege environments to allow AoE RMs/Seraphs to tank/level more effectively (big pulls, big xp!)
Prevention: Flag it so it can be cast with both a knuckle (non-siege) and stick for better tanking ability for BPs/Force Masters and RMs/Seraphs
That's all I've got for now, I'll add to it as I come up with more stuff.