I'm very familiar with Maggie 3.6s. I would not recommend a tube amp for these. Although some of the bigger powerhouses sound good but with lots of heat and heft. Your Hegel is probably a decent amp. I would add a tube pre-amp, a good one.
Tubes and less sensitive speakers
I love the sound of tube amps but I use Maggie 3.7's. I have tried an 45 watt tube amp and while I loved the clarity of midrange, I missed the low end slam, even with a sub. Is there a tube amp out there that matches well with Magnepans? I am using the Hegel H360 and a friend recommended Coda high current amps but I still am thinking tubes.