Android :: Replacing Sense Apps For Functionality

I have a Droid and accordingly, have all of the stock Google Apps which come with Vanilla android. I work in the IT department at a University, though, and we're trying to decide on policy regarding the syncing of mobile phones and the level of support which we offer to customers. Android phones have been a burden because of manufacturer customization. We've had many issues with Galaxy users, motoblur users, and especially Sense users, specifically related to syncing properly with exchange servers.I've only just realized that the manufacturer customizations are not just skins, they replaced entire apps, such as the email app, with what seems to be inferior apps. Vanilla Android, with the stock email app seems to have no trouble syncing to the exchange server. On the other hand, the Sense app, for example, will not. Instead of recommending fixes for each manufacturer, we are recommending the use of Touchdown (which is 20 dollars and it bothers me to have to recommend one of the most expensive apps in the market).I know that the stock app has no issues with Exchange sync of calendars, contacts, and email. Is there any way, on a non-rooted HTC phone for example, to replace the sense app with the stock app?Worst of all is the fact that instead of finding a resolution to the issue, the school is recommending the iPhone, stating that it is "more compatible" with the school's server. I know this isn't true and hate sending business in Apple's direction, so I'd really like to help find a resolution to this.