Troy,
What boat(s) are you talking about?
No beachcats designs were based upon self-tacking jibs.
I know of no beachcats which originally came with S-T jibs since their first production year.
Many designs, including the F18s and F20s, originally came with small jibs.
They were able convert from an overlapping "normal" jib to an S-T jib of the same area.

An H20 is an older design with a large overlapping jib which does not easily convert to Self-Tacking.

Many boats, including monohulls, didn't come with spinnakers and are raced/sailed with them regularly
and their balance has not been destroyed.

NO ONE builds a beachcat that is specfically, 100% optimized for a spinnaker.
It would be a total failure because a buoy racing boat w/spin, spends more time and covers a longer distance UPWIND.