Good, at least what you have is working now. I definitely would avoid buying more WIFI devices until project CHIP moves forward and there is a more uniform standard for how they work and communicate across platforms. Wifi devices generally rely on a cloud connection to the company that made them, and if that fails because the company goes out of business, or just decides to go in a different direction, you end up with a useless brick.
For wired switches, there are a lot of options that use Zigbee or Zwave, and I would recommend those since they run on a universal protocol that will work with other hubs, and connect to a smartthings hub. Most work with stock handlers for basic function, but some you need custom code. I always recommend the Inovelli switches, and they have their own people that supply the custom code needed to work with smartthings, with great instructions and support, but it appears their dimmers are out of stock right now. If you’re looking for just on/off switches without dimming, they have them in stock now for only $28 from the link below.
Outside Inovelli, a lot of people seem to like the Homeseer switches. I personally don’t have those so can’t really say. The GE/Jasco switches are popular, and those are mostly what I have from starting home automation several years back. I’ve also updated a lot of the custom code for those to keep them working in the new smartthings app (just do a search in the community for them), but I have mixed feelings about Jasco and many have reported issues with the Jasco switches failing.
There’s a lot of talk on the community about different products, and I’m sure others can chime in on their experience as well.
Inovelli link below: