I agree, the TTC does not need to be bland to just blend in but it should not clash with the other theme around seven seas lagoon or bay lake. It should be designed with the expectation of outlasting the current styles of architecture, as to not looked aged after a couple of decades.
Personally I like the look of the THSR Hsinchu Station, and that elements of it can be used as a new ttc. The sail covering most of the station could be fitted with solar cells to power the ttc and hopefully some of the monorail lines it services. Along with that, there would be the opportunity to buy merchandise for the weather outside without having to waste that time in the parks.