Sounds like you need to do some serious research to find a long arm quilter you can work well with. You will want to see examples of their quilting. You want to make sure they will respect your quilting ideas. If possible bring photos, or pictures from magazines showing what you have in mind. Plan on sitting with them and taking some time to explain what you want. If they don't want to do this, get someone else. Since it sounds like you have lots of tops, choose one that is less 'heirloom' than the others and have that quilted to make sure that you both have a good understanding of what you want before giving them one of your more prized tops.
As far as stiffness goes, a quilt with dense quilting doesn't necessarily mean that it will be stiff. Batting, backing, quilting thread and the amount of piecing all play a role. And remember the batting determines the maximum distance apart the quilting lines can be, so you need to choose a batt that will support the amount of quilting you have in mind.
You should be able to get a quilter who will work well with you and finish your quilts beautifully.