I'm no expert by any means, so I'll give you my guess, and maybe some other more experienced can chime in. If you can list your ingredients and procedure, it might help you get a clearer answer too.
I noticed when doing extract kits that whenever possible, adding extracts later in the boil helped to keep the color more accurate. This might be especially true if doing partial volume boils with top off water. If you were using LME, then removing from heat when stirring it in and making sure it is completely dissolved and mixed in might also help. Since it is a tripel, I would imagine that it is not hop heavy, so I believe the later boil malt additions shouldn't affect your hops much.
As for the alcohol flavor, I'm not sure to be honest, but I would probably let it age a bit more.
Hope this might help some, and if I'm just totally off, then we'll both learn something.