Elderly male rat - am I doing everything I should be?

My rat Memphis is now 34 months old. I've had him since he was one month and he has been a healthy rat his whole life and even into his old age he hasn't had any major problems, only things like small abscesses and HED which he's adapted fairly well to. I do an overall check twice daily, once before work and once when I get home. I check and clean penis plugs and have safety q-tips for his ears, saline solution for any abscesses, and I clean him with baby wipes daily as well as a weekly soak in warm water to get off any extra dirt. He gets a little bit of low fat, low sodium unflavoured soy milk mixed with banana baby cereal once every three or four days for extra protein, extra lab blocks and of course fruit and veggies, sometimes if theres left over food from dinner he'll get some chicken or fish for extra protein which he loves. He lives in a single level cage where he mostly just sleeps and eats now as he's much more interested in snuggling rather than playing. I take him out probably for about 2 hours a day but with breaks every 20-30 mins in case he needs to go to the bathroom since he cant hold it like he used to. I also leave lab blocks on the bed and have a cup of water beside the bed that I offer to him once every fifteen minutes or so since he has a hard time getting in and out of his cage without assistance. Is there anything else I should be doing to help keep him comfortable in his old age?

That all sounds pretty good, except the protein. Rats should have very low protein since protein is bad for their kidneys. Your lucky you rat has been with you for so long that's a long run for a rattie.

I always thought elderly and baby rats needed a little extra protein?? Maybe it's just babies... and yeah Im so thankful for his long life, especially since he and his brothers were from a pretty bad backyard breeder in Hamilton before I knew anything about rat rescue. One of his brothers died at the age of 7 months from mega colon, his other brother passed away in February at 2 years 5 months old of an inoperable tumour and Memphis is still going strong. I know the chances he'll make it to 3 years are kinda low but to know he came from a bad gene pool and that I've taken good enough care of him to make it almost 6 months past expected life span is something that Im really happy for.