Answer to question 1 = No
Answer to question 2 = Yes
Your RTL rims are the same as the Sport rims except the Sport rims are painted black on the inside. Therefore, if you're willing to pay for it, you could have these professionally painted, machined and clear coated just like the Sport rims.
All Ridgeline stock 18" tires are the same Michelin LTX which included on the RTL, Sport and SE. The SE rims are from the Pilot Touring but put on the Ridgeline SE.
J