Armour sets can be stronger than random or unique equipment, and get a bonus if you have multiple pieces of the same set equipped. Lots of people do use and recommend certain sets, I just found that usually what I could find or buy was better than the equipment sets I could complete (in a couple cases there were sets that were about as good as or better than what I was wearing, but the bonuses were not as well suited to my character as what I had, or to get the full set bonus I would have to use a different weapon, etc).
Armour sets have fixed stats (you can change/upgrade the enchantments).
When you start D2:DC, at least with the Steam and Larian Vault versions, a 'launcher' window should come up first asking if you want to play the normal mode or developer mode, then it starts the selected version of the game and gets to the main menu. IIRC the GOG version has separate shortcuts for the normal version (which it places on the desktop) and the Developer Mode (which is just put in the D2:DC start menu folder).
In Windows Explorer, if you browse to the install folder '..\Divinity II - Developers Cut\bin' there are 2 executable files: Divinity2.exe is the standard version of DKS, Divinity2-debug.exe is the Developer Mode (right click drag and drop to the desktop to create a shortcut there, if desired).
If you start the developer mode (there will be a red warning message on the left side of the main menu screen) and load/start a game, you can hit the F11 key to open/close the Developer Mode cheat window.
Anyone help a newb with Warrior build ... ???class question! (mage advice and links to related topics)
Stat Point Distribution: What's the best way? (for a mage)
With my ranger in DKS I never saw a random bow worth considering once I got up a few levels and could use the first unique bow (I also used other unique equipment, and sometimes individual pieces from sets). I did sometimes reload a little bit at merchants to look for something useful from them, but their inventories only reset (other than predetermined items) when you go up a level, so that limits the amount of reloading you can do. Some special chests I reloaded for, but generally found that not worth the effort compared to just playing and taking loot as it came.