HSAs, HDHPs, and Budget Plans

I've been working with a couple of practices on different versions of the concierge / High Deductible / budget concept I think has a lot of potential traction in pediatrics. Given that there are a couple different possible scenarios, I'll start with one that most folks can recognize.
Here's the scene: January/Feb of 2008. New mom. HSA with a $5K deductible. HSA account is empty (employer hasn't filled it, they emptied it last year, whatever). There are two problems we are trying to solve:

1. We want to make it easier for patients to pay their bills.  Most of them will do a better job if they never fall behind and that initial hit in Year 1 is a doozy.
2. More importantly, we want to drive the patients to your practice for their important medical care.  PCC has plenty of practices who have seen a significant drop off in patient volume with the arrival of the high deductible health plans.  That's fine if it's for the runny noses, but if you're a mom skipping the 1m visit because there aren't any shots (which I just witnessed last week...again) you're making a bad choice.

How do we manage this.  Begin with what we know.  The average family like this will generate between $2-4K in revenue for your practice. Here's a rough idea:

In that first month, alone, your practice is likely to rack up a few hundred dollars in charges.  That six-month visit, with all the shots - a doozy. Your patients are stressed - they have large, immediate, out-of-pocket expenses.
To help them and yourself, create a simple financial plan whereby you charge the family's HSA account $250 a month for the first year for all of the above services (I included vaccines!).  If there are additional services rendered (more sick visits, for example), you can add those to the monthly bill.  The parent gets a nice, steady charge that is usually well below the amount to replenish the account.  You give them incentive to use your services and find value in what you provide.  And you start to rebuild the relationship that you have with your patients, keeping the middleman at bay.
BTW, if you don't include  immunizations and make your patients pay for them out of pocket, the number drops to something like $170/m!
Tell me why this won't work. And note that I snuck in some counseling and home visit at this price!