There is an addon that allows the use of wireless access-points as point to point bridges. But... if you think going down this route will help server load, then I am almost certain you will be disappointed.
Some people do mention AE cables (the basic fluix cables) as causing fps hits, and recommend using the covered versions instead.
But as for server load I strongly believe you are wasting time on the wrong things. Instead of I would concentrate on:
- mobs/animals(AI is the number one worst resource hog in the game).
- machines and automation doing unnecessary things(like OP farms and quarries gathering resources that noone will ever use/that just get voided).