I'm the wrong person to talk to
I have had the DA*300 for about three years and it is absolutely superb. I couldn't recommend it highly enough. That said, I have just bought a new HD55-300 as a lighter long WR option for an upcoming overseas trip; it will allow me to leave the 50-135 and 300 at home and free up space for other goodies.
Sell one or even two DA* lenses? Really? What are you thinking? The build quality is as intoxicating as the IQ.
I also couldn't imagine selling my DFA100WR, although I'm not a frequent macro shooter either.
By all means sell the 55-300 and O-GPS, but they won't really balance the budget from the DA*300 purchase....