Hardware advice for new setup

Hi there,
First post here so please forgive my lack of experience!
I’m looking at installing a solution based around home assistant for heating control.

I’m looking for something local (no cloud if I can get away with it) and something that plays nicely with Home Assistant generally.

In the first instance I’m looking for a simple solution - one zone (whole house) and time based heating schedule. However I would look to expand this is the future to include multi zone hearing (room level potentially) and presence detection.

Reading online has led me to one of the below as being my best bets:

Or
https://www.screwfix.com/p/drayton-1-channel-wiser-thermostat-control-kit-white/7785v

I’m base in the UK with an existing combi boiler (a Baxi) with an existing “dumb” wireless thermostat.
Home assistant would be installed on docker on my pre-existing Ubuntu server.

For this first foray into home assistant I’m looking for something with a back out plan (so I don’t end up with no heating next winter) but something I can build on in the future (hence my z wave thinking).

Comments/suggestions welcome to help steer me in the right direction.