The difference between episode 8 and 10 is that in episode 10 there will be full branching. In episode 8 you could go through the whole episode and not notice the branching. The only difference was the final few scenes. The problem is that we don't just have 5 branches now: Maya/Josy, Others, Sage, Jill, Bella, but many more. Each branch is divided into 2-3 branches, not to mention the completely bloated branch of the Others. So freeroam is a logical way to solve the branching problem without creating a lot of scenes. So I'm guessing all three freeroams will be bigger than usual. They certainly won't be as huge as the freeroam in episode 9, but I'm guessing they'll be on par with episode 7. And this was indirectly confirmed by DPC, saying that he needs to create a lot of scenes and renders for the freeroams.
But of course there are doubts about the connectedness of the scenes and their storyboarding. Given how messed up DPC's flowchart is, I expect to see a lot of logical inconsistencies. Something similar was in episode 8, when MC suddenly appeared in scenes and scenes in general ended halfway through (like the concert). In episode 9 too, the ending left a strange aftertaste. It was like the game was cut off halfway through, morning comes and...the credits start. No trademark intrigue and some cheap surprise twist like DPC usually does.
Freeroams are not intended to solve different branches problems, etc. They are the problem themselves in such a branching...
DPC is still have to create a lot of alternative scenes outside of freeroams. Everywhere. EVERYWHERE. Classes, campus, etc, etc. Sometimes it's just different facial emotions of characters to reflect their mood, or just using less renders in dialogues here and there, because they are shorten if we are not on particular branch (or no dialogues at all). We seen it a lot of times in EP9 and it's very easy to extrapolate it to any other scenes and events outside of freeroams.
Let me explain it better. Let's imagine some future freeroam(s). We already know how it would look like and was realized, while we have experience with EP9. On one hand... adding some characters here and there while you have a prepared environment and assets is easy. It takes less time to create and mess with. On other hand... while renders growing insanely because of different scenes with characters, their different emotions, probably costumes or clothes, circumstances, etc - we are (as players) are still at the same place, at the same event, moment, etc. Such type of branching and its inevitability grabs a lot of "renders" while providing close to zero unique content. I don't have an idea where do you see a solution here or what solution do you mean.
I think we already seen how the REAL branching works and looks like. And I hope it will be done in a such way. EP4, in short. We start at absolutely different environments, we have absolutely unique scenes and even sub-content. For example, we can visit Pink Rose if MC stays with Derek, while this option is not available with Sage and Bella. While at the same time we visit classes and other common events shared between all branches. That's the most complex thing. Because instead of playing with characters positioning, etc at the same event and place, DPC have to create an unique scenes. It takes much more time, but such content is MUCH more valuable than extra 4-5 images per each 1 for different branches at the same event/scene. It grabs the same amount of renders, but brings absolutely different expirience and joy to the player.
But... In EP4 branching was about staying in different places, because MC was being literally homeless. At the moment MC is a DIK, he live in DIKs mansion and have his own room. So, probably all unique scenes will be dedicated to spending time with particular girl(s), etc. While MC room is a part of different "freeroams" (just remember how much freeroams we had in DIKs mansion in the past in EP5-8).
Finally, don't forget, that some content just not possible and compatible depending on chosen branch. For example, what players will get on Bella's branch instead of parties? Bella won't attend to them. Probably Jill too, while she can attend to some of future parties, I don't think she will participate in all of them. It's easier with J&M and Sage, since they are all HOTs now, they are always visit each party, etc, but here we step into the relationships permutations and variations.
Regarding large freeroams - 95% of them would probably be a different parties, which we will have in each future episode. They will still take a decent % of renders and episodes "space", but I see all future branching and it's realization same as we already seen in EP4. It just can't be done in any other way. Differences - that we will not be able to get lewd scenes with girls outside of chosen branch with potential exclusions like Sage threesomes plans, cheating, etc.