They were not as proggy as Rush and could be poppy at times - yes, "Rush light", but also could have a very heavy sound (check out the live albums). I saw them in the late 70s / early 80s multiple times at wide ranging venues from smaller room to arena here in Ottawa. They had an unbelievable stage show for the times (I think this was Gil Moore's doing). The earliest show I remember (would have been around 77 - after "Rock and Roll Machine", pre "Just a Game") - it was a low ceiling'd level floor'd room like you would go to for a conference meeting. The stage was all white with Rik having 3 white Marshall full stacks (even the heads were white) - the stage and Triumph lettering above were outlined with sequenced lightbulbs (looked like the pre-florescent 100w household bulbs - ancient by today's standards, but effective), and they made great use of strobe lights for drum / guitar solos (loved that effect - not so much seen any more) - not to mention a fair dose of pyro, all shoved into this small space - very memorable. In the larger shows that came later (ie "Progressions of Power" tour - 1980), they were one of the first bands I saw that made significant use of laser based lighting. Around that time, I was in the "Triumph is better than Rush" camp - having seen both on multiple occasions (well really it was a who's the best guitarist: Rik Emmett or Alex Lifeson discussion since I was interested mostly in guitar, while my drummer friends debated about who was the best drummer Gil Moore or Neil Peart - what there was total agreement on was that, for us, these 2 bands / 6 musicians combined were the best in the world for everything). In those days I/we really had no clue about genres: rock, heavy rock, southern rock, metal, prog... - it was all just about the bands / musicians that made the biggest impact on us - as I've gotten older, I guess I've become more of a prog head since I still listen to a lot of Rush - not much Triumph any more.
I believe Rik Emmett still tours periodically on his own and he was teaching music at one of the colleges in Toronto for quite a while not sure if he still does. Gil Moore created Metalworks studio in Toronto - not sure if that's still going but it was one of the bigger studios in Canada and there was also a MetalWorks production school.
On the vid above, listen to how little gain Rik uses a lot of the time.