I don't like glitter-boats at all, so my advice won't be biased toward either brand.
Will the add-ons you plan doing to the old boat make it as good or better than the new boat?
Will the add-ons be equal in value to the extra cash you would need to get the new boat?
Can you afford either option?
I have never understood needing the newest of something, if the one you have works just fine. But everyone is different, and I'm sure you have your reasons for wanting a new boat. I mean, who doesn't love a new boat, right?
If it were me, I would keep my current boat if it was in good working order, and spend the extra money on goodies that I wanted, to make the boat fit my needs.
Right now, my 17ft Lowe is in desperate need of a new front fish finder. But that being said, I'm not going to go out and buy a NEW Lowe boat, because it comes with a new fish finder mounted to the front.