Never lose hope AnimeHolic, the tentacles need your energy.
A Japanese friend of mine on Twitter clarified awhile back, the survey asked for a remake a both 1 and 2, he provided this:
The rough google translation was "I want you to make a perfect full remake of a mysterious bug (primary, eroded)!"
So we can probably assume "Primary" = Inyouchuu, "eroded" = Shoku, not to mention the comma between them. The first game wasn't as big as TB's games after that, granted I'm sure the new remade artwork and additional scenes/DLC made it a bigger undertaking. Shoku was huge with like a thousand CG's, but I'm sure they might change things up and it'll be the same size as the remake, Goku, etc.
It took me two years to get the Shoku bonus OVA with Ouka and Kikuka after the first two episodes...
There was also a two year gap between episode 1 and 2 of the original Inyouchuu OVA, too bad that wasn't worth the wait!
Never stop dreaming, the bugs keep coming!
I'm not worried at all, we usually only get ~2 TB games a year anyways. So we always have to be a bit patient. The collection sold better than they expected and had a second print run. Inyouchuu has easily become TB's biggest mascot and Aojiru's trademark series, there's no way they're done with it. Plus they have a lot of setup they can do for a potential Inyouchuu 6, with Ai and the White Cat Brigade.
I know it's hard being a tentacle/monster hentai fan. Gotta be patient...
EDIT: Also Shoku got many re-releases, you should get it off DLSite or something. Works fine for me on Win7.
INYOUCHUU FOREVER!!!
Also I wanted to share with you guys my new Asagi creation in SC6:
https://my.mixtape.moe/tywxhy.jpg