As others have mentioned the Philips bulbs are about as good as you can get but they are also the most expensive. And that you can save money by going with the IKEA lineup but the quality isn't as good. But your third option is Innr bulbs which sit perfectly in between Philips and IKEA for quality and price.
TLDR
Philips - best quality / most expensive
Innr - medium quality / middle pricing
IKEA - lowest quality / least expensive
Note: when I say the IKEA is the lowest quality, I just mean between these three. They are still miles ahead of any of the no-name brand crap you can get on Amazon.
Definitely Zigbee or Z-wave instead of wifi. Once you start to build out more devices you will be glad to not have gone down the wifi route.
I went with Zigbee and have Sonoff SNZB-02 temperature and humidity sensors in each room that have been absolutely flawless since the day I installed them, and they last about two years on a single battery!
I would obviously recommend them but I don't have any experience of other thermostats or of Z-wave.
I did also install smart Zigbee TRVs on each radiator but I don't rely on the internal thermostats of them as they don't accurately represents the overall room temperature.