My random orbital polisher has a variable speed from 800 - 4000 opm, 150 mm pad. Very similar to yours.

I use microfibre bonnets for the polishing compounds and terry toweling bonnet for the final buffs. I do have dedicated bonnets for each compound.

For the harder to reach places I hand rub the compounds using Meguiar's foam applicator pads, and then the microfibre bonnets.

The Polishing Compounds I use are:
Kustom Grit Step 1 - Superfine Abrasive paste is equivalent to 50,000 Grit, and their Microfine Grit Step 2 - equivalent to
100'000 grit! This is an Australian product I saw at a carpentry store - so I thought I would give it a go.
Meguiar's Ultimate Cutting compound,
Mequiar's Scratch x.

I'm still trialing and experimenting with the process.