When I was considering the BMX route, I found very few frames that supported disc brakes or could fit a suspension fork. I think there were maybe 2; 24” models.
The bike was going to be for my wife. I switched my plan toward certain model years of the Specialized 24” Hotrock kids bike. Has disc brake posts, super low top tube, and enough room for a shark pack under the downtube without interfering with suspension travel (I was considering going with 20” rims for better climbing, which makes clearance even less of a problem). With higher rise bars, it would look a little BMX-like.

Top tube distance similar to a large BMX frame, but with longer chain stays.
If it was for me, I might still consider a BMX since I already have an ebike, but for her, stopping is important and there are parts of the bike path that are fairly bumpy due to tree roots under the asphalt.
I still haven’t pulled the trigger on building it, since she only shows lukewarm interest. That means I’ll need to look for a decent paint color in case it turns into mostly my bike.