My understanding from watching various YT reviews of the Mega Drive Mini is that the Mega Pi is slightly smaller but more substantial feeling, so I imagine that would put the kibosh on the "Tower of Power" thing sadly. That said, I noticed that Retroflag recently brought out a nice addition to the SNES version which adds a (purely cosmetic) cartridge to it. I wonder if they're eyeing up the Tower of Power and considering it as a potential future product addition to their Mega Pi? Would be nice if so.
God I love my Mega Pi. I give it a wee cuddle every day you know. It's nothing weird.