I saw a tactical article on another 40k blog and thought I would post one here. Mine focuses on SM/CSM and Khornate Daemons. I will also discuss how to take objectives from the opponent with these armies.
First I'll say that I am not a fan of 5th edition Space Marines. To me they are boring and you tend to see a lot of the same lists... Vulkan Marines seem to be the most prevalent. I don't think that scouts are good at holding objectives. They are roasted by heavy flamers and are vulnerable to assaults. A 2+ cover save doesn't help you in either case. Scouts have their uses though but that is another discussion. To me it's obvious tactical Marines embarked in an obscured rhino is your best bet. Your opponent will first have to wreck/destroy the rhino before they can get at the Marines. Tactical Marines in a rhino can pillbox - that is, remain embarked and fire the heavy weapon from within the safety of their transport. I am not an advocate of combat squads, so no razorbacks. A combat squad dies quickly from small arms fire, ordnance and other shooting... Plus they will fold quickly in an assault. So to me one of the best units for holding an objective is a full squad of tactical Marines inside a rhino. I'll go so far as to say they should be equipped with a lascannon, meltagun and power fist. I'm not a big fan of multi-meltas for tactical squads as they are short range compared to the lascannon. The meltagun is there for duality, the squad can tank hunt if necessary. Finally the power fist is there in case they are assaulted. If you are trying to hold an objective then choosing to break is not a good thing. Sure you might be able to counter charge the next turn but there is also the chance that they won't fallback far enough and will remain broken.
_Chaos Space Marines_
CSM has a lot more choices and I think a good one is a squad of lesser daemons. Sure they are not inside a transport but they are relatively cheap and if they go to ground in cover they have a 3+ cover save and are T4. CSM also have access to their equivalent of the tactical squad but you rarely see them as there are other choices that are stronger all around. Nurgle Marines are probably the best choice and with the ability to take two meltaguns they never need to leave their rhinos. We all know that Nurgle Marines are very popular now. Thousand Sons are not worth their points and Berzerkers were made to take objectives, not hold them.
You only have one choice, Bloodletters. It's not in their calling to hold objectives but that's all you've got. The best thing to do is take large squads so they'll hold up to shooting. They are also T4 just like CSM lesser daemons. No one wants to charge a large squad of Bloodletters sitting in cover... They'll maul you. The flipside is just to land them beside enemy objectives and take theirs, more on that right below.
This is much harder for Space Marines as compared to CSM and KDA. It's not like a squad of tactical Marines are going to roll up in a rhino and blast a squad of Plague Bearers or Nurgle Marines off an objective. So first you have to clear the objective with another unit(s) and then move on your tactical Marines. Units such as Berzerkers, Nurgle Marines and large squads of Bloodletters can do the job by themselves. One of the greatest strengths of any daemon army in general is that your entire army arrives via deep strike and is not affected by deployment. That's extremely powerful if you stop to think about it. People say daemon armies are random due to which wave comes in first and bad scatters. If you know what you are doing it's not bad at all though. What you need are strong units that can endure one round of enemy shooting then it begins to work in your favor. If your secondary wave comes in first then you'll just have to play mote conservatively... It just takes a little longer, that's all.