^ I like Logopolis quite a bit myself. It's not the best regeneration story but I think it's up there among the best.
A few things were nonsensical. Not sure how the measurements of a different police box helps the Logopolans fix the chameleon circuit. The idea of partially materializing underwater to flush out the Master's TARDIS doesn't seem that well thought out either!
But, it had some very intriguing ideas and I liked visual style. The tone was appropriapately somber. Etc. Good stuff!