Indeed true for the first and even I dont think even the second one is gona be a very good decision becuase the little calculations involved by pupil like fan boys will be as poor as one can expect from a 5ht grader so better to do the alteration which really can put some +ve effect not really at least psychologically..
best option I see so far is to Put a Dlx/RP RIM+Tyre if a 125 can bear it so then there would be no issue with a 150 (even better Grip and no loss in any thing)