The controls are telling. Half the buttons are used to either move or select. The other half execute attacks and special abilities, or reference recent info and objectives. Getting movement and selection right is crucial for any RTS, so they're appropriately favored here. A tap to cycle through bases, another tap to cycle through heroes. The left bumper select all units, the right bumper selects only what's immediately visible. You can still highlight individual units or double-tap to select all of a type or even tap and hold to select by touch.
Build menus are mono-layered, so you're never deep-drilling. Click on an interactive point and you'll see all there is to see, no secondary or tertiary command lists. Once you've mental-mapped the buttons and digested those construction outlines, it's pretty hard to get lost, because everything right there on the surface.
Take bases. To build one, you tap a button over a preset build zone. This brings up a circular "dial" style menu. Nudge the thumbstick toward the "build base" option to initiate the process. Once the base is complete, you've got a predetermined number of open spots to populate with structures that furnish resources, units, and ability upgrades.
Click on those structures and in the menu dial-wheels that pop up, units are always on the right, abilities on the left. You'll never have to nudge through more than three per side (or up to six per selection wheel). It's game design 101: Keep your interface consistent.
There's an interesting intel wrinkle during skirmishes that's automated as opposed to strategic. No technology involved, i.e. no radar dishes or satellite uplinks. Instead, an "A.I. Advisor" you can toggle on or off occasionally chimes in to warn you where the enemy's most likely to assault, and what they're bringing to the party.
If you speak RTS, you'll want to disable it, but it's probably there to give players with less experience in the genre a leg up, and there's definitely a casual angle here.
Speaking of, computer RTS wonks like to sermonize that your left hand belongs on the keyboard. That's fine, but they're called hotkeys for a reason. Some folks prefer to play using the mouse alone. I'm one of them.
Still, pair both types off for 1v1 competition, and the keyboard commanders tend to dominate.
Console real-time strategy games, by contrast, are intrinsically equalizing. Everyone playing Halo Wars on an Xbox 360 has to work with the same number of buttons. Winning at a console RTS has to be about effective strategy, not QWERTY shortcuts.
Speaking of strategy, building fast and quick-assaulting without upgrading or securing additional strongpoints seems like a great way to lose in Halo Wars. Maps have multiple locations for bases, pre-located sentry towers you have to fight for, and supplementary resource generators you'll need to grab as quickly as possible, then guard while seesawing between flash points.
Two minor criticisms:
1. Camera rotation needs an inversion option. As it is, the screen rotates around a central axis in the direction you push, or counterclockwise. I prefer clockwise rotation around units, or what I think of as "orbital" camera motion. Unfortunately there's no option to swap this in the setup control screens.