On picking the club, I would base it a lot on the flying site. Are there trees? Which way is the runway oriented compared to the sun and prevailing winds? What is the land beyond the runway? Is it swamp or fields, and if fields, how high are the weeds? Is the grass mowed regularly? How about the porta-potti? Other amenities? Do you share the field with the helicopters? How big an airplane can you fly? How far is the pits from the runway (more is better, a lot better)?

I have several clubs myself to choose from, and one is just a much nicer flying area than the others. (This is assuming you don't mind the drive. In my case, since one is much closer, that's where I fly a lot.) The next piece would be how crowded the flying site is. If you are more interested in flying than socializing, go for less crowds, since it's better to fly with fewer airplanes in the sky. (Of course if socializing is your thing, choose accordingly.)

If you can visit regularly, you may be able to get a sense of how strictly the field is run. Neither way is necessarily better, but you'll want to find one that fits your own style.

On the instructor, they are usually volunteers, so I'm not sure you'll have much choice. I don't think there are many bad ones out there, so it's mostly going to be a matter of convenience. Who is available when you are?