There are normal homing keys included I think?
The two R3 keys in the middle.
Can't be sure since they aren't labeled in the kit image, but I think those might be scooped only? So what do you do if you happen to prefer barred
Anyway, if the goal is to have the barred homing keys stand out visually (in addition to being physically different), how about keeping the triangle shape but making it slightly different, e.g. by making the flat inner edge of the triangle on those keys subtly curved in towards the middle? Something like this:
Just a random idea. Probably bad.
@ZLightningZap: Could you confirm which keys in the kit images are homing and what type they are (scooped/barred/nipple/...)?