I have never used filter socks so I share your concern with how quickly they get will get clogged, I will go to foam prefilter if this happens.
Initially I was thinking I could get the filter inside the stand, but after some thought, I think it would be much easier to have it sit behind the tank for three reasons. (1) Easier access (2) larger filter/tank (3) I will have room for storage under the tank.
My goal is to have this wet/dry as the only filter since I am tired of cleaning canisters

, but if needed I will add an FX5.
I am going to try and pick up a 90-125 gallon in the next few months and since I have time, I can wait for a good deal.
I do like your rubbermaid filter and I know that many on here have done similar things with excellent results, however, I do not trust the tubs to hold up over years of use and it is well worth it (to me

) to have the tank made of glass for peace of mind. This of course is only my (maybe some what ignorant) opinion
On a different subject, do you know how to cheaply cut a hole in glass?
I found some bits online, but they are in the $50 range and it seems silly to buy something like that for a single use
