It seems like most everyone will tell you mech is king. If you want to get ahead of the curve then I challenge you to not to play mech. Mech is easy. Not mech is hard. You can take the easy route and go mech. I think you can play without mech and win. Here are some anti mech lists that are very strong:
•Daemons - There is no options for any mech in this codex. Soul Grinders are armor clad walkers but they are not mechanized. Mechanized is running units in transport. The rules for armor are incredibly good in 5th edition. There will be a big swing when 6th edition is released. It's the way of the world. The pendulum swings both ways.
•Foot eldar - Blackmoor has proven this list. Eldar are inherently mobile without mech. You save points in your army when you forgo mech. It's a challenge not to play mech but it can work. Eventually the pendulum will swing back away from mech. If you opt not to run mech now you are giving yourself a big head start.
•Battle Sisters with inducted IG - one my best friends who plays 40k created this list. In the right hands it is very powerful. Marc has demonstrated the ability to take just about any codex that is deemed weak and turn it into a monster. You often hear people say how awesome are dark eldar. Marc was the first person to win a GW GT with dark eldar. Everything that people do now with dark eldar is simply a throwback to what Marc has already done. Raider rush is definitely mech but not necessary to win. Dark eldar is a very old codex. Nothing has changed except for the rulebook and all the other armies that have received one to two new codices since the release of dark eldar.
This article is a direct tie in to my articles about strategies & tactics.