Are you in the US? It does matter as far as what’s available.
With regard to switches, there are a number of good brands. For reliability and quality engineering it’s hard to beat Lutron, which is neither Z wave nor Wi-Fi, but uses its own proprietary protocol. There is an official integration with smartthings. And if you happen to have an iOS phone, there is also a HomeKit integration which is very good.
https://www.amazon.com/Lutron-Wireless-Lighting-PD-6WCL-BL-Assistant/dp/B00KLAXNC6/
EnergyAvenue is a no-frills warehouse operation which usually has the lowest prices on Lutron devices. Quite a few community members shop from them.
https://www.energyavenue.com/Lutron/PD-6WCL-BL
Or of course you could use an in wall micro, typically Z wave, and then you can use any switches you like. I like what Mike Maxwell did with his, but you could also put them behind a regular dumb switch.
I personally really like the look of the Eaton Cooper zwave switches in black, and they are very reliable, but for whatever reason they never came out with a zwave plus line, so they are the older generation. Still nice switches, the main feature missing is they will have a shorter range than Z wave plus devices will.
The device class features FAQ discusses what features a zwave Switch might or might not have and why people might care about it. Start with post 40 in that thread for the light switch discussion. 
( The topic title is a clickable link)
There are a lot of Wi-Fi switches that have come on the market in the last two or three years because of Amazon echo and the fact that most mass market consumers don’t want to fuss with a hub, but most of these are cheap Chinese made brands with no safety certifications.
Read the following thread and it discusses the issues in detail based on a 2019 article from CEPro. It should answer most of your questions on that subject.