While these points are all accurate, I find them comparable and RnR actually an "easier" ride than SM. SM has no head or upper back support and it's jerky. RnR cars are state of the art - full head support.
Those inversions on RnR are no big deal - because you're going fast, tit's in the dark, the support, and the smoothness of the track. A friend of mind rode it the first time and didn't even know about the inversions until someone told him about it after getting off.
I was a ride baby before going to WDW and like OP at that time going on Thunder and Splash were big accomplishments for me. From that perspective, this advice.... Do NOT skip RnR - it's the best ride on property.
I actaully think ToT is the second best - I've done drop rides at 6 flags parks and ToT isn't as bad because you're inside and never really see how high you are off of the ground. You know you're not dropping until the elevator moves to the front of the building and engages, and the ups and downs are pretty thrilling. I find the 6 flags rides terrifying because of the hights. Also, the ToT themeing, and the hotel/queue are spactacular and not to be missed. Again, from a ride whimp, I'd say go for ToT.