Does it really do any good to send Reps any correspondence if they are NOT MY REP?
Same question for Senators.....
Social media is fine, as it is by nature a medium beyond a district or state. Correspondence, OTOH, tends to work best for your own elected representatives. If you to send something outside your district/state, you may wish to try to find a way to tie yourself to the area (business, vacation property, visiting a few times per year, etc.).
Correspondence with lawmakers for whom you're not a constituent is better than not sending the letter, of course. I've sent plenty of emails to such lawmakers and did get some replies, including personal ones. Others hit me up with an automated reply regarding my not being a constituent. So, it's quite variable.
Thanks for taking action!