My TrackMania² Stadium maps ( also available on my Fun “ SpeedTech „ & More 80K server : maniaplanet://#join=_Harest@TMStadium@nadeo ) :
They mostly have for theme Wall Rides / tunnels (aka tubes) / loopings, +/- in the speedtech style.
► Deep Down [tm.mania-exchange.com] (Remake) : Made for the A&C2 [www.maniaplanet.com].
► Let's Ride [tm.mania-exchange.com]
► Twinster Helix [tm.mania-exchange.com] ( video ) : Made for the CCP 2018 [tm.mania-exchange.com].
► Manifold Island [tm.mania-exchange.com] ( video ) : Made for the CCP 2019 [tm.mania-exchange.com].
Regarding the server, you can add maps on it [www.i-volve.net] . There's some rules and they'll be tested before.
I opened 6 additional servers, RPG ones, main one being RPG - Beginners & More : maniaplanet://#join=_Harest_RPG@RPG@tmrpg .
Others RPG servers are a server per map difficulty (Beginners, Intermediate, Advanced, Expert) and a private one. You can find them all by searching "Harest".

Global Game Jam 2018 (Theme : Transmission) : Trans Mission [globalgamejam.org]. Genre : Narrative / Typing game. You play a trans on her mission to gain self-confidence during some of her college days.