Yeah, oddly enough colour matching doesn't seem to be a big problem for the wig-manufacturers. If you send in a sample of your hair, you rarely get a bad match. What is a problem is the false hair fading at a different rate from your real hair, producing a mismatch. That is something you always need to be alert for if you wear a hairpiece, and wearing a full wig gets around that problem.
I can't really get to grips with what you are trying to achieve with your hair. Most of us hair-wearers want the hair to look and feel like our own, and we wear it full time and want it to be undetectable. It doesn't sound like you are so fussed about those issues. The conventional wisdom is that you try to keep as much of your real hair as you viably can. So if it is only the hair on the top which is gone, you just replace that (with a toupee / hairpiece) and keep the good stuff. You only need a full wig if your sides and back are too far gone to be usable.
Either way, for a decent result which feels like your own hair (to yourself and others) you need to get rid of the clips and use glue and/or tape. Not only does it feel better and stay on more securely, but it means you can use a fine lace base on your hairpiece. With clips you need a stronger base, which is also coarser and more detectable. Clips are only good for when you are uncertain whether you want to wear a hair replacement, or if you want to be able to take your hairpiece on and off very frequently (eg if you are an actor, or you prefer to sleep bald). They are not suitable for full-time hair wearers. IMHO.
