There are 3 main categories of players in TM. There is the mass, that just enjoy hopping on a server (or solo campaign) and playing some tracks, the creative part, which you managed to satisfy (mostly) with editors and the other tools found in MP, and the competitive part, which also has potential to be satisfied.
So my idea to save the franchise is to implement a total free to play model for all the games in ManiaPlanet. How it would work in my head: There will be Free accounts and Premium accounts. The free accounts would be able to play online forever, with no time limit and maybe a small part of the Solo campaign (All white tracks maybe?). The premium accounts will be able to access the rest of the content: Map Editor, Replay Editor, Skins, Avatars, Custom nicknames, Full Solo campaign. Basically, everything besides online servers are locked for free accounts. Buying an environment will give you access to the respective environment's map editor, replay editor, solo campaign, access to planets and the other premium features.
The next step is to simplfy the current ManiaPlanet interface. A clean, simple and modern interface would benefit a lot, and I do mean A LOT. My idea would be to ditch the current title system and just have only two main interfaces, the TM menu and the SM menu. I made a concept (for fun

Last step would be for Nadeo to hype up the update, and get as much media coverage as possible, in order to inform people that a new release is happening, and definitely a cool trailer to show what the game is about


In short, I believe that a model similar to this will be able to bring ManiaPlanet, ShootMania and the new generation of Trackmania to a really big number of people. The more I think, the more I see that Nadeo has most of the "ingredients" to turn TM into a great success, they have good graphics, they got fun gameplay and just needs a bit of an overhaul. The keyword should be Accessibility.
I kept thinking about this for a long time, and thought that maybe sharing my thoughts here would be good. Fingers crossed Nadeo will not only be able to attract a lot of people in MP4.0, but also keep them. I don't mean this thread to be taken as a "hey, go do that right now!" but more of a way to discuss possible methods to re-popularize the Mania games. Thanks a lot for reading!