Hi Dave,
fantastic!!
I'm from Ticino (the italian part of Switzerland)
..good to see that somebody will visit Lugano.
I agree with Mark, Lucerne will be a good trip.(don't miss the transportation museum!)
Also consider to visit the St. Gotthard, if you're up for military stuff, bunkers and co to be find there.
If you are more keen for the Roman Era, than visit Augst, near Basel (Augusta Raurica in Latin) Old roman garrison Fort on the lime (the border with germania) in August there's a big rehenactment show
..very popular.
Also in the area there is Windonissa
now Windisch
.ancient roman town with anfitheather.(they have a homepage type "augusta raurica" and you should find it).
Zürich, Basel, Bern all have military museums with nice collections af armours, especially late medioeval.
In Ticino itself
..yeah you have the Castelli di Bellinzona, the ruins of the castle in Mesocco
..no much more what's military.
In the french part of Switzerland there are also Roman settlements or towns and nice castles (Estavayer-le-Lac, Montreaux, etc)
Hope this helps you
.
Alex