I have to agree with
@BlueLoo the setting of the lock shield is more than balancing with a modern gas boiler.
A TRV takes time to open and close, so the flow through the radiator needs to delay it heating up fully long enough for the TRV head to act.
I also agree big radiators are good, as it means you can speed up the heating of one room when required.
I trimmed the lock shield by starting at closest to boiler upstairs, turning radiator off, then once pipes cold, on a little until one pipe got a little warm, and repeated moving out from the boiler, but this was only a start point.
I think the proper way is to measure in and out temperatures, I tried with one of these
they can be set to read object temperatures, but the results fluctuated wildly so did not work. Using the electronic head I get current and target,
so I used that for the final little bit, if current exceeds target then close a little, once done I was surprised how well it worked, the model of TRV head I used was OTT with anti-hysteresis so set at 22°C at 7 am and 20°C at 8 am or it would take to 10 am before fully warmed up, and it could not stop morning sun in bay window causing over heating, but in the main once set it was spot on, no need for a wall thermostat to control room temperature, although still need one to turn boiler off to stop is cycling on a warm day.
On removing the electronic heads now lock shields set, and replacing with liquid filled mechanical type, they also worked spot on, but hard to set with those heads, as *123456 means nothing.
The liquid filled TRV has a range, as at 20°C it will be wide open at around 3.5 and shut at 2, so 20°C is some where between 2 and 3.5 so would say best option is get one electronic with target and current displayed and move it radiator to radiator to set them.
I have 9 electronic heads, and I can set them so before coming home first kitchen warmed, then dinning room, the living room and finally bedrooms to speed up the heating of rooms being used first, but this does not work with geofencing.
I find geofencing a pain, it will for what ever reason not detect my phone, and turn the heating off. It did work last year OK, may be because now turned to google control rather than nest, first went wrong when high winds damaged EE mast, but since then done it many times.