I'm curious about this myself, since those seem the natural visually-synnergizing sets and I've been wanting to do plant on a controller. The thing I was wondering if is nature affinity tends to be a little redundant on a controller, since nature seems to be somewhat focused on healing and with a good amount of control people shouldn't generally be taking much damage, but the powerset does seem to have other helpful abilities. But I havn't looked into the powerset a lot yet, I was waiting for the final version to be live in case there were changes.
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Character List
I am not sure about the synergy with Plant to be honest.. Of course all I know is what I have read on the wiki but nature has -damage and -to hit debuffs which would seem like it would be counter productive with seeds of confusion.
Saying that I still will make one because.. well it seems fun!
I read some where else that Dark/Nature is a beast. I am curious to hear more about that to be sure!
Dark/Nature sounds like a blast. Personally I am leaning towards a earth reclaiming character with Fire/Nature. With the proc in bonfire and natures strong debuffs/buffs looks like a great pairing and very visually pretty.
I'm thinking of illusion/nature affinity or earth/nature, myself. Both would provide me with very support-oriented characters, which I'm looking to make. Concept for both is already worked out, so I'm just waiting until I have more time to test the synergy of the pairings. Really excited for nature affinity, though!
Talen_Lee: Taking absorb pain is like branding 'H' on your forehead. Which stands for 'Failure'
Scarf_Girl: ever since I six slotted my Rp with cyber/emo Hami-O enhancements they haven't been able to touch me
Gonna have to go Plant/NA for maximum awesome and theme reasons.
When there is no room left in Hell, the Dead shall walk the earth.
I'm thinking a grav/nature controller. Probably won't synergize that great but it sounds like an interesting combo so what the heck. 
I have concepts for both Plant/nature and Dark/nature. Don't care much about synergy really, though with plant and dark it is hard to go wrong. For the Dark/Nature I have been wanting to do a Witch concept for the longest time and this seems perfect!
Anyone have any thoughts about Electric/Nature? I'm idly thinking this because I started an Electric/TA I didn't like but didn't give the set much of a chance. I've already done solid characters on a lot of the other control sets and I don't like to repeat myself.
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Character List
Has anybody run this up to high level in Beta? If so, how is it looking and how will it pair with plant/ (I'm expecting great things ... )