It could be worth considering creating a 'Legacy' package for some of these older games, at a higher entry-cost. These older games have less users, thus less demand - so why not offset that lightened demand with a price increase.

I would easily pay 50-100 EUR a month for an APB framework from a trusted source. Add in some other legacy games that aren't that popular anymore; I'd pay up to 150 a month in appreciation for the upkeep of those frameworks, for games I still enjoy.

Hopefully a larger price differential can make such a concept for a package, for these older games with less demand, feasible.