You have a lot of things here, so let me attack each thing step-by-step:

> This thread (and especially this post) are interesting to me because I have considered -- on and off since I was a teen -- designing/making my own clothes (to meet my special needs) and, recently, toyed with the idea of doing something like that as a business (and all but dismissed the idea out of hand as just too much trouble).

Don't give something you are passionate about up! Please contact me if you need help getting off your feet. I will be happy to help you with as much advice and direction that I can.

> Any thoughts on finding/making cotton-silk blend knits (for women)? I rarely can find this but it is awesome when I can.

Cotton-silk is difficult and expensive to process. In knits, you'll only find this in the high-end. Zegna does the best big-name cotton-silk knit fabric that I have seen on a garment. If there is a store around you, go to their polos and take a look.

Why silk? If you want a soft hand feel, look at modal. It is a stronger fiber than rayon, significantly softer than cotton, and processes about as easily. In today's cotton market, it is only marginally more expensive. A cotton/modal blend is magnificent.

> Silks are too expensive and too fragile for my lifestyle and rarely come in knits. They shrink horribly when washed and just don't stand up to my lifestyle (which is rooted in keeping everything clean enough to stay well in spite of my medical condition, and dry-cleaning is not acceptable as I react badly to the chemicals).

If you are talking about woven silk shrinking, then you are doing something horribly wrong. If you are talking about knits shrinking...well, that's difficult to explain. Shrinkage is controlled in fabric finishing by "setting" the fabric while holding it at the dimensional stability you are after. Most garments that are 100% cotton in the US/Europe will have between 7-9% shrinkage in both length and width. This means the dimensions will shrink by that percentage after the third wash.

> Most knits are cotton-polyester, not acceptable in my book.

100% is by far the most common yarn to knit with. Cotton and polyester have to be dyed in different processes, so to make a solid color (dyeing both cotton and polyester as opposed to just one or the other) is more expensive than starting off with cotton yarn and just single-dyeing it.

Incidentally, the whole "heather is the new black" phase in the States confuses me. Most cheap heather garments are a cotton/poly blend and suck. Look for 100% cotton heathers--they are dyed at the fibre stage (before the yarn is spun) and are significantly better garments.

> I don't wear polyester....etc...etc.

Polyester, when processed correctly, gets too little credit. It has better drape and appearance than cotton, and is orders of magnitude stronger. It obviously has different uses.

> So I have played with the idea a bit. I looked up a site called "French Rags" because I know they do mass customization and they sell knits. But it turns out they use a yarn blend I don't want (IIRC: cotton-acrylic). Good quality affordable clothes is really tough to find.

I don't know French Rags, but a good-quality store wouldn't use blends like that. What is affordable to you? I can make recommendations.

> Nylon and some spandex is also acceptable for me. But polyester is absolutely unacceptable, most other synthetics are not really very acceptable, and 100% cotton wrinkles so bad and therefore is too high maintenance.

Viscose/rayon, modal, bamboo etc. all count as synthetics. All of those are significantly superior to cotton in all aspects of feel, coolness and drape.

100% cotton doesn't wrinkle bad if you get well-processed fabric, and understand how to iron clothes properly. The key is medium-high heat and plenty of moisture in the form of steam. If all else fails, iron your clothes with only 90% of the dryer cycle. On all good steam irons there is a button that squirts water. If you've ever wondered what it is for, then this is it. If there is a hard crease, just squirt it with water and run the iron over it with steam and the crease will be gone.

I don't own a single "wrinkle-free" shirt or pair of pants. I buy good quality dress shirts and pants, and only wear 100% cotton (100% linen shirts for the summer). If you are willing to commit to 7 minutes of ironing per garment, then there is no reason that you shouldn't have crisp clothing.

Plastic-based synthetics are harder to iron than cotton.

> Most of the clothes I buy is 95% cotton, 5% spandex or 90% nylon and 10% spandex. I don't own an iron but can't afford to show up at work all wrinkled -- it's a violation of the dress code. Knits with a little spandex generally avoids that issue altogether.

Ah, no iron. Buy one [1], since they are cheap and handy.

Spandex knits shouldn't make such a big deal. One trick is to use a setting on your dryer (if you use a dryer) usually labelled something like "perm press". Make sure you use 2 dryer sheets for anything over a 5kg dry load and plenty of softner, and then take the clothes out of the dryer the moment they are done and hang them up. Your clothes, after a night, should lose their creases just through gravity.

Protip: good quality suit jackets and blazers should never touch an iron via this method. Don't let that ugly iron shine ever appear on your clothes.

> So, I have thought about a DIY approach to solve my problem and also thought that the amount of work involved, well, it might make sense to do it as a business rather than jump through all these hoops to dress one person.

It's a great idea. With the kind of upscale market that you are looking into, you could definitely look into getting value-added garments and fabrics sourced from duty-free countries.

Good luck! Please let me know if I can offer you any advice on starting up. My contact information is in my profile.

[1] http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Dap...