I don't see it this way, Ren. I'll post again the opamps arrangement:
And a very good single-to-dual DIP8 adapter board with sockets pre-installed:
https://www.cimarrontechnology.com/browndog-021001-single-to-dual-op-amp-adapter. Of course, you could find similar adapter on eBay at a fraction of the price, just not sure about the quality (perhaps with DYI this can be done better and cheaper than eBay). Now it might worth doing some measurements prior to purchasing these adapters, because I'm not sure will perfectly fit inside the PLAYMATE.
However, what's really important is that combining the same socket for I/V and LPF makes this the shortest audio path possible, so I only see a highlight here.