Glass components in weapon trap are very easy to setup if you have sand (if you don't, just hack the files and transform one soil into sand) and protect very well at first yar.
If your corridor is long enough I can handle sieges from 5-6 squads easy, including trolls and other nasties stuff

My corridor of magma doom is already something that takes much more time and resource if you want to make a big one so don't focus on it first I would say.

Water works well for the killing yar, but then you need to clean up the mess after, which can take quite a lot of dworf to clean up all the bodies/cloth/weapon.
That's why I like magma, nothing left to clean ^^