Keep in mind that matched status will only work for about a year, and you can only match once ever at most programs. Do you only hotels stays for one year??? Do you have plan for after that? (IHG Plat can be had outright with just a credit card, as can Hilton HHonors Gold. But I think those are the only two that give mid- or top-level just for holding a credit card.) You'll need 35 nights with the credit card (50 nights without) just for Marriott Gold (most but not all of the benefits of Marriott Plat). You'll need 25 (23) stays or 50 (45) nights at SPG to requalify for SPG Plat (numbers in parens are with the credit card).

So in light of that, combined with the relatively small footprint of Club Carlson, combined with the fact that you have to very top tier of Club Carlson just to get a free breakfast (while you can get the bottom tier with just a credit card, I don't know if you can status match to the very top tier), yes, I think that would be diversifying too much. In fact, it seems to me you're already diversified for what will be "too much" possible to requalify for. It may make sense to sample these programs, yes, but you'll presumably want to narrow the field down for future years.