Wow, thanks for the list of resources. My problem with most robot arms are either they have small payloads, accuracy isn't very high, are too slow, or software support is terrible. Do you have any specific suggestions for 6DoF? The MG400 looks to have 4.
What payload are you looking for? Cartesian Gantry’s are your next bet if you want to handle higher loads. Eg. Epson vt6l is ~14k but I’m sure you can build a gantry system to handle higher loads for a bit less!
Dobot software sucks though, I ended up programming it in python. It’s definitely not on the same level as say a Kuka or Yaskawa. Epson seems like the best value out of all the higher end arms. Software looks good, the arms are built well, has a long history in industry, and price is decent