if the NFP performed better then GS you can bet that they will tell the devs to make it work with new mechanics in that format.
Although that might be true, but it doesn't mean that NFP would have been successful regardless of GS/RnF. In fact, I believe NFP wouldn't have been half as successful, if Civ6 didn't have any Expansions. Yes, most NFP stuff don't require any Expansion, but they are so much less interesting without them. So IMO, the success of NFP is built on the Expansions, not surprising given that they are "Icing on the Cake".
to anwer OP's question; I think a formular similar to Civ6 would be fine. And I would accept an NFP style like DLC Pass if done well (like without breaking the Game with Bugs), though ideally for me would be :
- an NFP style release of 3-4 small DLCs (No Game Modes, but Scenarios - with a 3 Months Gap like others have mentioned) in the first Year (to keep Fans engaged before 1st EXP).
>> 1st big Expansion.
>> 2-3 small DLCs/Scenarios before 2nd Expansion (so there won't be a Year of silence like between RnF and GS, or GS and NFP).
>> 2nd big Expansion.
>> 4-6 NFP Style DLCs.
>> Final Game Update Patch.
An Example on how that would look like:
- let's say Civ7 releases on October 2023 (with 18 base Civs)
3 Month Gap
- Jan 2024 DLC Pack 1 (2 Civs)
3 Month Gap
- Apr 2024 DLC Pack 2 (1 Civ)
3 Month Gap
- Jul 2024 DLC Pack 3 (2 Civs)
6 Month Gap
- Jan 2025 1st Big Expansion (7 Civs)
6 Month Gap
- Jul 2025 DLC Pack 4 (1 Civ)
3 Month Gap
- October 2025 DLC Pack 5 (2 Civs)
6 Month Gap
- Apr 2026 2nd Big Expansion (7 Civs)
9 Month Gap
- Dec 2025 DLC Pack 6 (2 Civs)
3 Month Gap
- Mar 2026 DLC Pack 7 (1 Civ)
3 Month Gap
- Jun 2026 DLC Pack 8 (2 Civs)
3 Month Gap
- September 2026 DLC Pack 9 (2 Civ) (celebrating Civ's 35th Anniversary)
3 Month Gap
- Dec 2026 DLC Pack 10 (1 Civ)
3 Month Gap
- Mar 2027 DLC Pack 11 (2 Civs)
Total Civs: 50 Civs (same as Civ6 has)
Total small DLCs: 11
Expansions: 2