“perfect” is a tall order, and different people will have different requirements.
One popular device that might work well for you is the remotec ZRC90. It has eight buttons, each with tap, double tap, and long hold, which gives you 24 control options. Works well for either wall mount or table mount. It’s about the same size as a single wall switch. Cost under $50 and is available in both the EU and US zwave frequencies. It identifies as having 24 buttons, so it’s easy to use with the official smartlighting feature or with core. The only issue is that the buttons aren’t big enough to label individually if that’s a problem.
Alternatively, a $20 Wi-Fi phone from Walmart running smarttiles might also give you everything you need. The negatives there are deciding how to power it (unless you just get two and swap them back-and-forth between the wall and the charging station). And the fact that there’s no tactile feel.
www.smarttiles.click
There are some other options as well, but I think those two are the closest to your list.
One thing you you didn’t mention was how many different scenes you want to get from one device. That could make a big difference. 