When I play I spend about 70% of my time in combat and the rest for training my merc and travelling. Learning the short-cut keys are essential and using the "Speed Up Time" when running across a map is very useful. So is holding down "shift" when scrolling the map. The "raise weapon" reduces your aiming time a lot. I only spend 6 sec when I use a sniper scope, and then only with the first shot. The second shot costs around 3 secs. But you only use scopes on targets that are far away. When dealing with enemies close by, use pistols or SMG's. When using an AR or Rifle at enemies close by, use "Hip Shot" or "Quick Aim". If you are expecting an enemy to come around a corner, use "Aim at Point". When the enemy appears you only have to spend 0.05 sec to fire off that first shot.
If you find the game to difficult and constantly getting hit, try different tactics, like "Fire and manoeuver" or set up a "Cross Fire" ambush. The faster you run, the harder it is for the enemy to hit you. Run for cover and "Prairie Dog" them to death.
There are a lot of these kind of tricks that makes this game easier, the more you play, the more you learn about them. As Barrabas said, it takes some time getting used to and to learn the quirks, but when you do it's soooo worth it. I've been playing this game for more than a year and I still play Brigade E5 from time to time. The re-playability of these games are great, the tactics you'll employ will evovle as your enemies gets better weapons, and so do you. This is a squad based tactical game, it's about testing and using your tactics in battle. It is not about delivering parsels to mayors
Some of the recent comment are from people that hasn't played the game through and might be of the "instant gratification" types. If you are one of those, don't buy it. But if you are like me and many others who love the game and genre, you know, "harder challenges = greater reward" types, this game is worth a try. I'm glad that there are developers out there with the cojones to make these kind of niche games, otherwise I'd be forced to play the mindless crap that 99.9% of the gamers would buy, but stop playing as soon as a "new" one appears.
Despite the bugs its a great game.
EDIT: I forgot to say that there are some very talented russian guys working on a mod that adds a lot to the game. The community is very much alive and will be for a long time.