100 bps are like nothing. Only in ATCS you can make some kind on defence with it and you can win. Problem is, there is not enough points to make forward base or 2 like alien can with 100 bps. Its important to humans to minimize walking time from human base to alien base.
On 999 bps servers, building is key element, not only securing reactor, more important even, make forward bases. It only needs repeater, medi and tesla, and lucyguy can make alot pain with it. If its nearer to alien base, more damage can such a small camp do.
And even on SD, builders are needed, repeater can be very effective blocker and gives energy ammo too.
I build mostly forward bases like so:

Point is, if one repeater is going down, second one is giving power to all buildings. On SD, you can replace blowed repeater.