Good, 20s are a good idea.
I hate speed bumps though, both in the car and on my bike. The ones that are just islands, rather than the whole way across, mean that drivers swerve to get them between their wheels, they cut in too close.
Forty Hill is a 20. NO ONE STICKS TO IT. When I drive along it I go 20, with a group of tailgating cars 2" off my bumper. When I ride along it they swerve in and out behind me trying desperatey to get past. FFS wait! It's only a couple of km long, and there are lights on the bridge half way down anyway.
There are 20s all over on my route to work, people simply don't observe them.
When I am Queen there will be stiff penalties for speeding in residential areas - proper loss of licence and freedom penalties (plus when they are in jail they will be put on a chain gang to build cycle ways), but I shall allow my subjects to go fast (faster than now) on motorways and other suitable trunk roads.
There will be no danger to cyclists, horsists, and footists because there will be proper alternative, convenient, pleasant, viable routes for them which are separated physically from the motorised traffic. On routes where it is not possible to separate squishy road users from hard ones, the hard ones will just jolly well have to slow down OR ELSE see above.