I use Nest Gen 3, all hard wired, easy to use (not quite so easy to set up) simple dial and display in centre. Yes it can use wifi and other wireless links, but it does not need to use them.
But the main consideration has to be the boiler. Worcester Bosch is not as far as I know OpenTherm, some Worcester Bosch can use their own ebus controls, but as far as I am aware the boiler you have is controlled by the return water temperature and the external thermostat is only there to stop boiler cycling when warmer weather arrives.
So the TRV's control room temperature, and the wall thermostat is placed in a room normally kept cool, on ground floor, with no outside doors, and no alternative heating, if such a room exists, so why does it need to be easy to use, when in real terms not touched for months.
If my boiler was a Worcester Bosch modulating boiler then likely would use a very simple wall thermostat, hard wired as you want it to switch as little as possible, £12 from
Screwfix, Flomasta EMP912MT if I wanted to program the heating then the Flomasta 22199SX but the latter is not what I would say is easy to use.
So in a care home the heating is on 24/7 and it does not need any timer, but most other homes want some sort of timed control, I don't like it warm at night, but do want it warm in the day, so easy of use, Nest remembers what settings I have used in the past and can learn what I want without my needing to go into settings, can you really get it easier than this
large display, and simple turn dial on outside, and it learns what you want. But not cheap.