1) Cosmetics for weapons: Yeah sure, it may be a major tell if my firey weapon is on fire, but I still want my FIRE WEAPON ON FIRE, DAMNIT! Naturally, make it where only X cosmetic can be used on X weapon, so no lightning weapons on fire or anything like that.
2) More ways to play: In Dark Souls, let's face it, he who strikes the most the fastest wins. Poison does jack all, Dex weapons rule (Not saying STR weapons are bad, but Dex are definately better), Regen is worthless, and on. The only real ways to PVP are Bleed, Buffed Dex weapons, or just straight up STR. Pure casters don't do much, unless it's a Combustion Pyro. This ties into the next point.
3) Better Rings: Rings should be all powerful character customizer tools, not these little dinky things we have now. We need rings that supercharge a certain aspect of your character, but leaves other low. For instance, turn our current bleed into 5% health for building up the meter, but with the Bleed ring it goes to 50%. Poison does 3 health per second, but with the Poison Ring it goes to 30 health per second. This would not only help buff things not used in DkS, but it would also force customization; you can't be a jack of all trades as it's just not as effective.