FWIW the last chapter actually makes me more optimistic about SIU's concepts for the series...but (a) I'm pessimistic about how well he'd be able to execute under perfect conditions and (b) I'm very pessimistic about how well he'll be able to execute under his current conditions.
If I knew SIU personally I'd be pushing him for the Xenogears option. This would be basically (a) jump to just before the finale, (b) do a long, highly-condensed flashback covering the main narrative points, (c) do the finale, ending, and epilogue in real time, and then (d) bring the series to a conclusion. Since I don't know him all I can do is mention it here, but that's IMHO the best actually-available option for SIU and ToG.
That said, it's still a pity b/c with just this last chapter a couple good possibilities came into focus.
One is that Leviathan having some Traum's memories is a good setup for a heel-face-turn vis-a-vis Traum (and then maybe other family heads). My pure speculation is Traum will turn out to have been Zahara's most-loyal/biggest-today because he deliberately sealed away all his rebellious thoughts/"good qualities" over with Leviathan...with this whole strange "heir arc" being some giant long-term scheme for Traum to eventually liberate himself from Zahard.
Another is the 12-month series: some kind of fetch for these always felt inevitable, but this tournament could double as a fetch quest—IMHO lots of princesses will show up, some of which will bring some months. (It'd make sense for the princesses to say they're there to defeat Baam, not marry him, but that's a detail—their showing up would be the point).
Another is the Androssi/Baam whatever-mance: actually moving that directly into a pairing has always felt like it'd be very out of place. That said, I could easily see SIU's concept here being "Androssi and Baam battle in the final round, Baam winds up 'letting her win' to save her some sort of situational threat/external problem."
Another is the low-key mind control angle SIU's been threading through: having 2+ 12 months active mind-controls the bearer into kill-crazy psycho, we saw some kind of reactive Zahard mind-control over Androssi (and, I think, Maschenny) back in the hidden floor arc, and there's a vague hint of Ren exercising a more-limited form of it way back in S1 (...that's a bit of a leap, but it's defensible). Combine that with the previous item and you get the Baam/Androssi fight either being a surprisingly-real fight or turning into one by surprise—would be fun.
A final one is Rachel: she's back, she's around, she probably used her 3 wishes, but whatever they are they aren't obvious. Given her general sneakiness and nastiness lots of room for her to show up and throw some real curve balls into the tournament.
You get the idea: if you take what's in play with where we're at we have the upcoming arc has a lot of really good potential. If you take a realistic look at how SIU's been executing lately, though, it's hard to feel confident in the upcoming arc. I'd like to believe he could go all "eat, pray, love" and return all "how SIU got his groove back,...but if I'm honest I think he should opt for the Xenogears option (and wrap it up in no more than one more year, tops).
