I've really grown fond of D-45 (Amber) Candi Syrup in certain Belgian styles. It adds a nice light toffee note, while helping get that dry finish that you want in a Belgian beer. I'd probably swap a pound of the base malt and one of the caramel malts for a pound of the D45.
Also, I think at least half of the base malt for any Belgian style should be a good quality continental Pilsner malt. Its just part of the flavor profile I expect in a Belgian beer.