I admire his sincerity in his career. Sure it would be much easier for him if he left the RA and began the royal appearance circuit where he tasted lager, watched personnel in factories, went to lunch with architects and all that but Will is made of sterner stuff and wants a real career. ( Anyone remember those folks who whinged that his training was for naught? )
While some courtiers are understood to be keen to build on the royal wedding "bounce" factor and hope that the Duke and Duchess will increase their public duties, the Duke, who was commissioned into the Armed Forces in 2006 and began a six-week stint in the South Atlantic earlier this month, is known to be sensitive at being seen to encroach on his father's role as heir to the throne.
Following a recent poll that found 56 per cent of the public would prefer him over the Prince of Wales as their next king, the Duke let it be known that there was "no question" over whether the Prince of Wales would be the next monarch.
http://www.telegraph.co.uk/news/uknews/prince-william/9076450/Prince-William-to-put-military-service-before-royal-duty.html
I'm glad he is not taking the easy way out. He and Kate will do a lot to support the queen's diamond jubilee this year but not overshadow his dad and wife. We can't have that. 
William can't sit in a corner and hide out lest he "overshadow" people. I somehow don't think the Queen thinks of her own grandson as "overshadowing her"--he is the future of the monarchy and both she and Charles should be proud of him instead of afraid he will "overshadow". Sounds dyfunctional if they truly think that way, IMO anyway
I don't think William thinks royal duties are "easier". If he did I doubt he'd have wanted to go to SAR in the first place. I think he himself likes a more private life, which has nothing to do with him "fearing" his grandmother and dad will be "overshadowed" by him. I think he himself wants to postpone royal duties for as long as possible which might not be the best move for the royal family as a whole.
Charles built his own charity and his royal work was not limited to 'tasting lager.' William can make a difference if he put in time doing charity work and reaching out like his father does. Royals CAN make a difference and not be lightweights "tasting lager."
Unless he wants to bow out of line of succession, William should figure that life is unpredictable and he may not have the luxury of going into SAR and not being seen doing duties all that often. If his dad or grandmother were incapacitated he'd need to fill in for t hem, for instance.