But having a bad (read nearly useless) skill is poor game design. Otherwise, she actually starts to decline at level 20, when she has to stop taking +stats, and start taking bad skills, while all the other heroes are taking useful things.
She's good, but she's not even close to OP. She's the squishiest hero around, she gets munched on pretty quick, and her 1.5 second directional stun is not going to save her when she's getting ganked from behind. I've never seen a nerf thread about her - she's rarely even mentioned in the lineup of great heroes.
Giving her something that allows her to explode other heroes is a bad idea. Giving her something that makes her even better at supporting her team or staying alive is a great idea.
I think she's pretty good right now, and I never ever pick Nymph's Grace unless I don't have an option. It's just too complicated of a spell for me to use on other people. Most people don't even know what I cast on them, and even if they do, it will hardly make a big difference. I'd rather have that slot be filled with something remotely useful, but plz plz don't nerf her
Nymph isn't even close to overpowered, and she does good work with support/pushing and can put out reasonable dps for a support slot. But Grace, while a cool idea, is useless in practice. I 'd prefer to see a passive defense rather than an aura, because she is very squishy. When I'm playing an initiator against Nymph, I usually initiate on her just because I can usually kill her with a tank build in just a few seconds on Pharaoh or Electrician.
Puck's phase shift would be interesting, in my opinion, or something like it that would give incentive to not burn her out immediately on entering a team fight.
Why not just have the Nymph's grace buff last 1 minute (with a 30 second CD) that restores .75 mana a second on you until you cast something (keep the 50 mana cost). Maybe have the mana restored go up slightly, so at max level you spend 50 mana to gain 150-200 mana unless you use your free spellcast. That way it's not a situational tool =P
I'd like to see something else that keeps up with her theme, and is a good ability that's not really to overpowered.
Nymphora plants a small blue seed in the ground. This seed will explode into a burst of mana in 4 seconds, restoring friendly heroes mana and draining enemy heroes mana, but dealing no damage.
mana cost 25 (across all levels) cooldown 45 seconds)
LV 1 : restores 75 mana / drains 40
LV 2 : restores 100 mana / drains 60
LV 3 : restores 125 mana / drains 70
lv 4 : restores 150 mana / drain 90
This would be similar to her other ability, but and would be pretty good, but not really imbalanced if you consider the cooldown and cast-time for the seed.
EDIT: You could also add a bit of chaos and unpredictability to this skill, making it so that it only restores mana, but it restores both friendly and enemy heroes. That way it would be a very situational skill, and it really would be a big gamble to use it in group fights, because you wouldn't know if it also ended up helping the enemy team.
i imagine this skill is a godsend for caster with low mana pools (behemoth comes to mind).
It can be very helpful, but it's to situational. The problem is that heroes will not always initiate with their most powerful spell, and you can't really wait to cast Nymphs grace until you think you know a player is going to use his ultimate.
There's also this chance that there are no heroes like Behemoth on the field, and giving someome 150-250 extra mana in a fight doesn't really change that much.
Granted, it could do the difference if you get first blood or not, but it still doesn't change the fact that you never really take more than 1 level on this skill.