Bee and butterfly garden

Hi, fairly new on here. I planted up a new clover lawn last year and I thought have I done the right thing. The benefits a clover lawn has out weighs the cons. This year I'm glad I did it. Loads of flowers some bees arriving now. We have a rhododendron which has now faded but that provides early food for the bees. Our lavender hedge is almost ready to pop. I took 6 Budleigh cuttings from a dying Budleigh and the are all doing really well. Can't wait for them to flower for the butterflies to come in. We haven't used any chemicals to get rid of green or white fly we are leaving them for other predators. The only draw back so far, grass is growing through our clover and I need to go out and trim it with shears to the height of the clover.

 

Do bumblebees not like clover? I have 1 buff tailed bee that visits but most are the common carder bees and loads of hoverflies.
Also what's the hoverfly/hover bee that looks like it fights with other bees in mid air?