My default template has:
Mastering chain with Selig Gain, RE-2A, Ozone 8 Advanced, and Tonal Balance Control.
Eight combinators for send effects, set up by default with three reverbs, a 3/16+4/16 pingpong delay, a basic 3/16 delay, and some empty ones.
Embertone Walker 1955 Steinway Lite piano, great for sketching out ideas on and frequently makes its way into my finished tracks.
Thor with a nearly default patch, just with a bit of subtle LFO detuning added.
Kong pre-routed with separate kick and snare mix channels and a spider to get sidechaining outputs from the kick.
This one takes only a few seconds to load.
Then I have a much larger template with
all of the above plus:
Una Corda piano.
Spitfire Chamber Strings legato patches and core articulations patches, routed to legato and core buses.
8Dio Adagio and Agitato strings patches, pre-positioned using Panagement and routed to a bus.
Joshua Bell Violin and Tina Guo Legato Cello, routed to a solo strings bus.
Century Strings multi-articulation patches, routed to a bus.
Olafur Arnalds Chamber Evolutions evo grids and waves, routed to chamber and bass buses.
British Drama Toolkit ensembles patch.
Orchestral Swarm strings high patch.
Albion V Tundra multi-articulation patches, routed to a bus.
Shreddage and Orange Tree guitars and basses and Embertone mountain dulcimer.
Embertone Sensual Sax, 8Dio Studio Tenor Sax, and 8Dio Fire Sax. Fire Sax has one track per patch (track folders and midi channels please!!) with the Kontakt instances in a combinator with a line mixer.
8Dio Claire Woodwinds legatos and arcs, with each instrument in a custom combinator to control the microphone blend on both patches at once.
Spitfire Symphonic bass flute and Albion One woodwind ensembles.
Spitfire Cimbalom and Harp for plucked orchestral instruments.
8Dio Propanium, Spitfire Celesta, Glockenspiel, Marimba, Crotales, Xylophone, and 8Dio Polyphon for tuned percussion-like instruments.
8Dio Fire Trumpet, set up in a combinator matching the one for Fire Sax.
A few multi-articulation tracks from Century Brass, routed to high brass and low brass buses.
A Europa init patch along with the Thor from the smaller template.
Percussion from Albion One, Tundra, Saga, and Rhapsody.
GetGood Drums Modern and Massive, pre-routed to mixer channels.
Neutron Advanced pre-routed on buses or individual instruments where each makes sense.
This one takes around a minute and a half to load, but saves me a lot of time that would be spent doing redundant setup work adding instruments, setting up buses, and balancing/EQing tracks.
I generally delete a significant amount of the template as I start working and figure out what I'm using or not.
I also have every Kontakt instrument pre-saved as an .fxb patch that can be loaded from Reason's browser. As a result, I can quickly swap any of these out for different patches from the same library or duplicate the tracks to add additional instruments from it. I also have project-specific favorites lists in the browser, comprised of libraries and specific patches that I'm likely to reach for on a given project.
(In case anyone from RS is reading: Track folders and midi channels pretty please. And the ability to save and recall pre-routed setups with multiple mixer channels and sequencer tracks.)