I'm going to restate my argument about the number of apps, as I feel I haven't gotten through to you yet. Say you are looking for a thing-a-ma-jig app. You have 700'000 apps to choose from. That number is simply useless, so you go to the "thing-a-ma-jig" category and get a list of 100 apps. So now what? Are you really going to download and evaluate each of those 100 apps? Isn't that highly unlikely? Instead, you will ask friends what they use or consult the internet to get a quick rundown on what is currently considered good. You will then start your evaluation based on that selection of apps.
For WP you might get 20 instead of 100 apps in that "thing-a-ma-jig" category, but that top-ten list will still have ten picks.
If those top-ten apps were picked from 100 or 20 apps really doesn't matter. The only thing that matters is that the apps on both of those lists are comparable in terms of features and quality.
Don't get me wrong, WP has yet a long way to go, as many apps don't yet match their iOS equivalents at this time. However, that isn't because WP has too few apps!
On the other hand, if a platform has 100'000 apps to choose from, and that number doesn't include a single useful app of the kind you are looking for (video editing), then the problem isn't the number of apps, but something completely different. Either the market isn't large enough to make the development of such an app a financially worthwhile endeavor, or the platform has limitations that don't allow video editing.
In both cases, the number of apps is irrelevant.
Personally, I wish MS would introduce a system to eject deadweight apps from the marketplace. Unfortunately, there is no chance of this happening as the number of apps (no matter how useless most of them may be) has been turned into a selling point.
Finally,
JP morgan chase does have a banking app available for WP, which is sure to come to WRT as well.