Yes. But it really depends on the situation and teammates you have...I mean. If your team is down in points and you think blindly rushing or pushing forward to be an all star with that fancy sniper you just OD'd (LMFAO) Then congrats! You just gave the enemy team more points and possibly (most likely) a fancy new Snippy Snipey. If you are UP in points and the enemy team is full of derpy mc herp n derps, then turtling is smart tactic. It wins. And Winning, BY FAR. Feels A FUCKLOAD better than losing.
Randoms with Randoms is Random. Nothing is going to make sense...however, be aware. The other team probably has a group party'd up and they are most likely communicating...and communication and teamwork is FAR more powerful than your lowly Rocket Launcher or SAW(which...if I'm using teamwork and communication...it'll be ours within moments, trust me.).
Respawns have never been Halo's strong point... I've been respawning into Sniper Shots, Ghost, Banshee Bombs, Tanks, Wraiths, etc...since fucking Halo 2. Get over it. You kinda just have to take the bullshit and roll with it.
Also. Pro tip. With the AR. Remember to fire in short bursts to get slightly extra range and so more of your bullets actually hit. Been that way for years.