After watching the demo, I get the impression that a good majority of the game will include playing with alot of high tech gadgetry (the jet packs, mini attachable rocket launchers, power suits, etc.) And I was wondering if their might be aspects of the game were you have really minimally equipped soldiers to work with..
Fighting the same crab monsters with really shoddy gear would definitely up the tension, and if there were ways to impose battles were you don't have access to all of your A ranked gear (or whatever you'd call it lol!) Perhaps when making scenarios in the campaign were it isn't always 100% optimal to load out all your squads with good gear, giving a good case for risk-taking.
Maybe instances could arise were secret mist controlled agents infiltrate your base and destroy your armories or having some kind of event that disrupts the flame throwers. Stuff like this to make you think on the fly could be a possibly fun way to add tension throughout the campaign (another mitigator to that tedium plateau of "we got all the good stuff and it's just a matter of grinding out the enemy till we win the game)
Having scenarios were the same mutant you've been mowing down with high tech rocket launchers and flame throwers is now suddenly empowered again due to some outside factor like this could be a cool, humbling moment for the players.