Its a basic problem. If a company makes a line up of 3 to five planes and supports them well then they will own that product segment. If they go further and introduce purpose built power systems and engines as combos then they will further own that product segment.
a company has to study the market segment and see the potential and then decide to enter that arena full force. Making one or two planes will only tip other companies off to enter that segment and potentially steal it from the first company.
It takes a serious commitment financially and the marketing department has to pull its weight to get the product noticed and desired.
Larger 80-90in planes are hard to live with I agree, they take up a lot of room and cost a lot, around $2500-3500 depending on set up. If you can fly a plane in the 60-70in WS range for half the price and buy quality scale models that would be great.
Ive been an advocate of full composite "60" size war birds for years and still nobody has made them. Were still in the 1980's with all wood planes that sell for top dollar! $999.99 wooden 1/5 Corsair? Really? Im working on a TF GS Corsair right now and still can't believe they get $750 for it.