Well, I'm sure you'll draw a lot of advice, but here's what I'll say.
Your DH can either choose to hold tight to his own opinion, or be swayed by the many, many of us on this board who visit WDW regularly and will say from personal experience: plan, be able to eat at the places you want to eat at the times you want to eat, and get the most out of your $$ by getting to do and see the things you want to do -- or, don't plan at all, wing it, and deal with being frustrated not being able to do and see the things you want to do and don't expect to eat at many sit-down restaurants at reasonable meal times. It's that simple.
The other aspect: do you enjoy the planning? Are you having fun thinking about your trip? To me (and my DH now understands and appreciates this, too), I am getting that much more enjoyment out of the $$ spent because I have a BLAST planning our trips.