What a cute loaf!
Unless a rabbit extremely, extremely obese, a single picture or description can’t reliably tell us whether a rabbit is overweight or not. Not being able to feel the spine is a good indicator of excessive fat; however, the best way to address this concern is with a rabbit vet.
I’m not familiar with the food brand, but the question of switching pellets should be based on nutritional value rather than rabbit weight– the amount of whatever pellet you choose is what weight impacts.
Here is a website that provides guidance of various pellets and whether they meet standards: https://www.therabbithouse.com/diet/rabbit-food-comparison.asp
I recommend comparing what’s on your pellet bag to what’s shown and making a decision from there.
The answers provided in this discussion are for general guideline purposes only. The information is not intended to diagnose or treat your pet. Seek the advice of your veterinarian or a qualified behaviorist.