I love the planters by Catdad Workshop, and their use of vase mode is impressive. For pots with built in trays, there's a 4 side holes for drainage, but this could be limiting for some moisture clearance, or watering from the base. (See photos)

I created this platform insert ‘puck’ to put in the plant pot before you add soil. It's basically instead of rocks or bits of bulk material gardeners may put in pot bases to let water clear out and roots aerate. 

I printed in 0.8 path on 0.4 nozzle for speed and strength, 0.3 layers. It's just for inside the pot. 

The structure walls are 1.6mm so designed for 0.4/0.8 nozzle/path.

The puck's top is solid in the model and printed face down, so set 0 BOTTOM layers on the build and then choose the infill of your choice that suits your plant/soil mix. I did around 50% hexagon 'infill'.

I printed in PETG and so bed adhesion was therefore easy, but if using PLA please check the hex ‘infill’ layers are going down well on your build surface.

It's a bit smaller the the inside of the pot to facilitate getting it out with a fingertip or tool if the pot is standing and you don't want to shake soil over the place, and so it fits even with filthy fast printing.