I currently have two very old rats, a small female named dewy and a large male named thunder. Over the course of 4 years I have had 20 rats.specally agree on the part about personalities - Dewy is timid and not very good about coming when called anymore (She might be going deaf), while thunder loves people and you don't even need to call him, he just stays with you. As for the immense varieties of markings, this is 100% true.. Every one of the rats I have ever owned have had different coloration and markings, with the exception of Willow and Rice, who were twins. As for smartness - I have showed 5 rats now and won 3 place each time- mainly because I didn't dedicate enough time to training. The winning rats could do amazing tricks, which is just more proof rats are intelligent and are fully capable of learning how do complex trick or even play small scale games! I have seen rats shoot a basketball right into the hoop (shrunk down version of course). I used to do lots of tricks ad shows with my rats, but as they grow old they prefer to snuggle up with you. Honestly I love to just read a book or watch TV with dewy perched on my shoulder and thunder on my lap - unless I'm reading, then dewy is on my shoulder and thunder is trying to turn the page. In fact, the only bad thing about rats I can think of is how short their lifespan is - average rats live only 3 years. It makes me sad to think Dewy is nearly 3 years and thunder is 3 1/2.
I don't plan on losing them anytime soon. We got them from a good breeder and all the rat we get from that breeder tend to live 4 years or so - the quality there is amazing.
Overall I agree with you that Fancy/Dumbo rats are not horrible sewer animals, despite what the awful stereotype has gotten people to believe. Noting is better than snuggling up with your rats
Sorry for the text wall.