Well he is eating and acting normal outside of you handling him so that should be some good signs. RIs generally sap their will to eat and there are other visual signs that show up.
What you call wheezing could just be verbal displeasure with you a big human grabbing his delicate sensitive self
Just keep observing for any signs other than wheezing. Oh and 411 grams at one year old is neither fat nor slim. I would just focus on seeing if you can get him more calm with handling. Limit handling to short session only a few times a week and just try not to over worry.