First timer here to this forum. I've been looking to get back into to fishing and recently picked up a pflueger president 6930 reel. Is this a good size for fishing rivers for smallmouth, or should I return this one and get the 6935. Also, what rod would you recommend to pair with either of the above two reels? I would prefer a one piece if possible and something that nots going to break the bank. Thanks

The 30 will be perfect. A 6' 6" or 7' M/F rod will work just fine. Something like a Berkley Lightning Rod Shock or Ethos from Academy would work perfect. 

I prefer the 30.

I dont see the need to ever go bigger than 30 size for bass.  it will hold up to 8lb mono fine and if you need heavier just use braid