Just wrapped up a pretty dreadful session of 4e tonight.
Had a 6th level encounter for 6 7th level characters. It dragged on. And on. The main target got taken out at the beginning of Round 2. The worthless mooks were boring to play and not much of a threat. I told the group that they could intimidate them into a surrender, but the party wanted to leave no prisoners.
The second fight had a 10th level elite enemy. And it completely demolished them.
I'm running the highest reviewed official 4e adventure. I just don't get it.
There is so much help out there on this subject Retreater. You just need to do some keyword searches and you should get a cavalcade of help. Look at some of my PBPs on here. Those should help. Meanwhile:
* 6 characters is far, far too many for any game (imo) and its basically a killshot for 4e. I would not GM any 4e game with more than 4 characters and optimally I would prefer 3 (which is the number for most all of my games, particularly 4e). If you have to GM for 6 players, 4e is not the game. Play something else.
* Spend some (at least 1 level worth) of your encounter budget on Hazards (which have 0 HP) that serve to eliven the battlefield array by amplifying Team Monster yet also being an interesting asset/danger which Team PC will want to interact with (eg; "force move Team Monster into").
* Reward movement, demand movement, instigate movement via interesting battlefield arrays (Hindering Terrain, central features, things to stunt with, the use of Controllers and enemies with Forced Movement, Fantastic Terrain that can be interacted with via Minor Action for a Buff which then exhausts the terrain).
* Make ample use of protected Artillery Minions that are hard to get to due to battlefield array (Blocking Terrain, Hindering Terrain, Altitude, Cover, or Soldiers) or Skirmisher Minions who can kite.
* Think about the game layer when you're generating combats first and foremost. Interesting decision points (tactical, strategic, thematic) are the beating heart of the 4e combat engine. If your personal sense of a narrow causality is how you're generating combat dynamics, its going to fall flat. Think gonzo tropes, think player character themes/goals, and think "what sort of an encounter budget and roster and array would make for a rich decision-space for each player."
* Embed an appropriate thematic Skill Challenge alternative Win Cons (like escort PCs or get to x square before the end of y round, etc) with special attention paid to the action economy of actions. Combat shouldn't always be about reducing Team Monster to 0.
* Demand your players pay freaking attention. Use a 1 minute egg timer for on-turn actions. They should be paying attention and have an action declaration ready the moment their turn comes up. If they're looking at their phones, being disrespectful to you and the other players, or generally not paying attention? Punt them to the freaking moon and bask in the glory of praise from every TTRPG ever who has had to deal with that sort of disrespectful, selfish behavior. But be sad for the moon because now it has to deal with it.
* Develop a script for your own bad guys that you can refer to quickly to resolve your turns if you're struggling with your own turns.
* Conflict ratio should be about 5 Skill Challenges to 2 Combats.
* Everyone should be playing goal-forward. Players should know what goals their PCs have and they should be put on an index card as a Minor or Major Quest that everyone can access (and should access as a refresher; perhaps as a beginning of session prologue the players each read aloud their pending Quests).