Awesome remake! I'm a great fan of the original, played a lot on Mame as well recently. No surprise my first ever sample cart for Pico-8 (first steps learning pico's Lua) is a "trainer" of the pig bonus stage with increasing difficulty (Amidus on lexaloffle).
About the bonus stage I wasn't definitely prepared for the odd bonus Hyppo stage (not in the original) is it your own addition or was it in some other remake/ports?