Maximaphily is a branch of philately involving the study and creation of maximum cards.
On the web site delcampe.com which is a France eBay-like stamp site that has worldwide coverage and members (perhaps more Europeans use this site than www.ebay.com/b/Stamps/260/"
>eBay? (except Great Britain)) (Perhaps that is where to best market your cards?) there is a maximum card set listed under Poland with the title:
12 Maximum Cards 1961 Number: Mi 1277-88, Sc 1029-40 Insects
ITEM NUMBER: 41479499
which looks like your insects. The seller is asking around $30 for the set.
(Mi = Michel = German stamp catalog)
(Sc = Scott = US and Canada stamp catalog)
Perhaps they just use the Scott catalog (or whichever catalog) for the stamp numbers?
DelCampe has a Maximum Card section under some countries.
Stanley Gibbons Great Britain Concise catalog (2005) that I have list P.H.Q. cards (Postal Head Quarters), cards that show the stamp enlarged, (1973 on) as mint or used. With or without a stamp affixed that is. Special cancels (first day of issue, special events) or handstamps make it worth more to different collectors.
I think most maxi (maxim,maximum,PHQ) cards sell on delcampe for a EURO (1.00 € ± $1.47) except if they have topical interest (like David mentioned above) which I think is the major market for maxi cards.
I kind of like the idea of them myself. I have tried to make some FDI ones but usually the cancel ink smears on the postcard, plus a rectangular postmark was used. It got the date on there but is not eye pleasing.
I think they would add a special touch of interest to a stamp collection. Or just to a special stamp, as a lead in or header on an album page or something like that.
The Great Britain dealers seem to have grasped onto the idea of another area of collecting interest and marketed it successfully. Some people just collect the cards.