I am still a newbie so take what I say with a grain of salt but i'll share with you some of what and why I have done.
there is also a groove on the bottom. should I put a strip there also?
I don't see much since in it, they generally don't attach it to the bottom anyway. It would just be more work.
you can or should use fishing line in the frame holes to add stability to the comb especially on deep frames.
I only use mediums so deeps maybe different, someone else will chime in with more experience.
With my mediums though, I did on the some of the first frames I built. However, since then I have stopped using fishing line because if they start to build crazy or off center it is really hard to straighten it out if they have started to construct the comb around the line. When you try to straighten the comb it destroy part of it. I now do not use fishing line so when they do start to go all wonky i just cut it of the top bar and use rubber bands temporarily until they secure the comb in the frame straight.
Hope that helps.