If you're saying they need to spend less on Final Fantasy, and more on Dragon Quest, I'd agree. Final Fantasy is already well known in the west. If a large Dragon Quest advertising campaign can bring it to even a third of FF's popularity in the west, that'd be great. Since SE is forced to make DQ as amazing as possible for Japan, it'd be a huge bonus getting western attention on top (the quality of the game will hopefully speak for itself).
Now, if you'd ask me if they should make more Dragon Quest titles, I'd say no. I think one of the reasons it has remained so strong is because there's a significant amount of time between each main release, not unlike how Nintendo treats its own solid IP's. They're treating the series just fine in Japan.
SE is spending way too much on Final Fantasy in general. They definitely need to diversify their lineup, sticking "Final Fantasy" on every game they make (see Crystal Bearers, or even anything Crystal Chronicles) is not the way you treat your top brand. Wada seems to think like Activision does nowadays - create one big hit, then farm it for all it's worth. This doesn't seem like a good long-term strategy.
It is time they start trying to either create some new IP's, or revive older ones. I know the issue is the home consoles' development costs, so I'd suggest giving the Wii a shot, but who knows...