Interlux does make a grit to mix with the paint to create a non-skid surface,
I used Kiwigrip on one Hobie and it worked out very well, I used masking tape to create outlines similar to the original Hobie layout.
The kiwigrip is gentle on your butt & knees too. some tapes are like coarse sandpaper.
84 Hobie 16 (sail #83460 84 nationals yellow)
85 Hobie 18 (sail #12610 *SOLD*)
90 Hobie 18SX (sail #668 blue/pink)
92 Hobie 18M (sail #14967 Generator/#17022 Baja Blues)
81 Hobie 18 (sail #4908 White)
(a boat or 2 for sale soon...)