Dear SemiNube,
not all butt plug bases are designed to have a proper function besides safety - many of them are shaped or decorated in a certain way for the sole purpose of being an eye candy - and that's wonderful.

However, there are certainly butt plugs bases that actually have a functional use. Toys like Spade here, for example, or this Vibroplug if you fancy vibration, have a T-shaped base with slightly raised nodules. Not only they hold up more securely, but they also provide thorough perineum stimulation, which contributes to orgasmic experiences a lot.

Also, the T-shaped plugs are indeed the ones best fitted for extended wear - they snuggle comfortably between the butt cheeks, providing you with some additional spur and staying discreet and comfortable during casual sitting or walking.

Bulky bases, like circular ones, or featuring rings, are super comfortable just for the extent of your session - after some time they might make you feel sore.

Hope this helps.
Best of luck!