Terwilligar, linking into South Campus LRT station, would be the first line I'd create.
Something connecting the south/SW main hubs, like Windermere, WEM, South Edmonton Common, Heritage Valley, Century Park, Millwoods. Possibly two lines there.
Whyte Ave, from Health Sciences LRT all the way to Sherwood Park Freeway, and into Sherwood Park.
112/111 Avenue, from Concordia University to the Telus World of Science, connecting with the LRT at the Stadium and Kingsway.
Kingsway - 118 ave - Groat rd - St Albert Trail, starting at NAIT LRT, all the way to St. Albert.
153 Avenue, from Clareview LRT to what will be Campbell Rd LRT stations.
97 Avenue, from the Garrison to Churchill
Not necessarily all should/could be BRTs, but can certainly be express, high level services.
Most of these routes could be targeted with relatively low costs and no big infrastructure spending (at least comparatively).
New member, long time lurker.
As you say, not all should/ could be BRT. In fact, a lot of these routes already exist as express or limited stop service, or are proposed.
The 97 St corridor has the 120x, plus the 110x to Downtown via 118 Ave/ NAIT/ 109 St, plus other expresses in the 97 St Corridor (130x, 150x).
Existing regional transit systems with limited stop service already cover NAIT - St. Albert, Downtown - St. Albert by St. Albert Transit and University to Sherwood Park by Strathcona County Transit, granted, frequencies have dropped off from what they were prior to Covid when high capacity buses on 15 minute frequencies was normal.
112/ 111 Ave. The existing ETS route 3 is effective as is and a relatively quick option. Concordia is not a significant enough trip generator to justify a BRT/ express route. Right now, in addition to the regular #101 route, all that Concordia rates is a seasonal community (short) bus route from Coliseum. Ditto for the Telus World of Science. Sexy suggestion for a terminus for a higher order transit service, but how would it be justified as a trip generator?
There was supposed to be busways as part of the original Terwilligar Expressway intended to be for a South Campus service, but, after the Provincial funding cuts I don't know where that stands.
Besides existing Strathcona County Transit service on Whyte Ave, the proposed center LRT was not recommended as part of the most recent City Plan cycle, but, rather a BRT is recommended. The Future LRT portion of the City's website still shows the Centre LRT, but, that is more or less dead at this point as I understand it. This seems like this is the most likely to actually end up as a BRT in some form (dedicated lanes etc) in the future at this point, depending if any busways materialize with the Terwilligar Expressway.
Falls Under EMTSC:
From what I recall about the proposed EMTSC routes in their business case they would operate more like express or limited stop services. Clearly, this would be the case with some of the former regional transit routes, like to St. Albert. The EMTSC does have routes that cover the WEM - Mill Woods corridor, and the 153 Ave corridor.
I believe the EMTSC is still aiming to launch in Fall 2022, so, we could see these services sooner rather than later.