League of Legends (LoL) Question: How is Nami?

I agree with Ramin Diako from before. My opinion is in general it is the nicests combination of many support champion abilities.
1. As every champion she needs to be mastered first to be useful to your AD carry.
2. But you need to also teach them (AD carries) to get closer in distance to combine the damage with heal that switches to magic damage on the opponent.
3. The skill shot stun is in fact hard to land (calculating in the delay), but since it can stun many opponents at the same time it is pretty op and can save from ganks if used well.
4. Ulti comes nicest when used unexpectedly or from a bush or behind a wall, when the enemy doesn't expect it.

Here a list of abilities compared
1. Passive - every spell that touches an enemy makes him slower and you as well as partner faster - compare to Lulu's that only comes from her Q
2. Q - stun better than taric although hard to land stuns more than one champ - compare to sonar only with ulti (R) causing longer cool down rate -
3. W - heal as effective as soraka's heal - Alistar's / Taric's / Nidalee's heal are weak compared - additionally it does damage and slow to enemy and can heal multiple champs if casted on ally while both enemy and ally in range
4. E - buff comparable with Janna's buff (not giving shield but additional magic damage and movement speed though - slow on enemy when hit by AD carry) - Lulu's whimsy (same here about shield..) and Karmas atk dmg buff
5. R - ulti short stun and slow not as OP but depending on situation can decide a team fight

She seems balanced to me.

AP she probably does decently, but Support is much better as her role.

I wouldn't play her as ADC..

I have been played Nami recently and I find that if, like me, you enjoy being an agressive support then Nami is one of the best champion you can go for.

Her abilities are designed to be engaging on your enemies, her Aqua Prison on its own can turn the tide (no pun intended) in any lane then adding the force of Ebb and Flow and Tidecaller's Blessing mixed with Nami passive she is easily a good team leader.

Nami is balanced. I wouldn't say she's underwhelming at all; she has a nice amount of CC, good buffs and a solid multi-target heal. Oh and Nami's ult is rightout ridiculous when utilized well.

she is good for many reasons:
1-u can heal and damage with just 1 ability
2-sweet stun , but hard to aim
3-rly good buff 4 ur adc in lane(+magic dmg for 3 next hit and also slow enemy)
4-long range ulti that makes u to start a teamfights
so if she isn't the best support, she is 1 of them.
sry 4 my weak english.

She gives a good combination of poke, sustain and CC. However, at the moment, she appears to be extremely underwhelming in comparison to other supports.

There may be a number of reasons for this - her cooldowns are long, she is a jack-of-all-trade-mistress-of-none (meaning that i might be difficult to find a niche spot for her in team composition), people haven't found the proper ways to play her.

Let's see what Riot thinks when they decide to address her (or not to address her if they think she's balanced). But at the moment: yes, she's extremely underwhelming.