As a radar controller, a main part of our job is to try to not make Tower’s life miserable. I know that’s a heavy burden to carry but that’s the cross you bear.
Tower only has two commands to initiate a speed change, maintain best or slowest practical speed. Whereas you have more specific speed commands where you can have aircraft maintain, exceed or do not exceed specific speeds.
If you see a conflict in spacing, issue a speed command before handing off the aircraft to Tower.
6.14.9 — Once aircraft are cleared for the approach, speed is at their discretion unless they are subsequently assigned a speed command. In this instance Controllers must use the “maintain XXXkts until X mile final” option (see 6.13.4 above).
You should never be in a situation where spacing is poor, but if you are, don’t hand off your dirty laundry.