I'll be ordering a hair system from TopLace soon but before I put the order together I need some help with some questions I still have.

The system will cover most of the top of my head and will leave about 3 inches of my own thinned / sparse natural hair at the front hairline (see attached photo of the template). My template includes a crown at the center back, with hair going forward. I know that it won't be a great look since my hairline is receding and thinning, but it will be a huge improvement over what I have now and I think it will be much easier to maintain and less detectable to others than a full hair system since the hairline is my own.

Questions
1) I have thin hair density and also thin/fine hair shafts. Can TopLace match my hair thickness with the sample that I send in? Otherwise, how can I specify how thin the hair should be?

2) People often mention hair density but usually not how thick the actual hair shafts are. What exactly does 55% density mean? That 55% of the lace is covered by hair? If so, then 55% density with very fine hair requires many more hair shafts than 55% density using normal or thick hair shafts. Also, the length of the hair plays a role in density/coverage as hair that's 6 inches long provides more coverage and density than hair that's 2 inches long.

Please help me understand how to specify density, hair shaft thickness while considering hair length in my order. My goals are to minimize hair density with a hair length of about 2 inches, while keeping the lace undetectable to others. Currently my hair is roughly about 2 inches long on top and maybe 1.25 inches on the sides and back. I definitely would like to keep my hair short, if possible.

I was considering going with 45% density in the crown, 45% at the front and 55% everywhere to make it realistic since I don't have much hair now. Will the lace at the crown be detectable with that level of density, 2 inch length and fine hair? If so, what density would you recommend, considering a length of 2 inches and thin hair shafts?

3) Should I go with ILace to hide the hair knots since my density will be low, especially in the crown and front? I've heard some mention on the forum of an ILace island, with SFS lace on the perimeter. Do you recommend this approach considering my template? I live in a hot and humid climate plus I'm active and would like to continue outdoor activities like swimming, diving, jogging, biking, etc.

4) I will be specifying some amount of gray to be mixed in, maybe 2%. Does that mean that I won't be able to color the system hair later? Does the white hair used by Top Lace absorb color from hair dye? If so, how can I color my system hair without coloring the added white hair?

Thanks in advance for your help!