Alpha Strike: Commander Edition will cover all unit types and their corresponding movement modes, attributes, vehicle specials, etc.
If you're looking for fluff, and a selection of good beginner-friendly chassis, TRO 3039 covers most of your common combat vehicles, fighters, et cetera across most eras. Some additional staple fighters can be found in TRO 3075. Clanners will want to check TROs 3055 and 3067 for their fighters, and TRO 3060 for vehicles. General infantry is more of a DIY thing (just make it easy on yourself and pull the stats for generic platoons from the MUL), but TRO 3085 and its Supplemental offers a charcuterie of specialized infantry units, and paired with 3075 offers a good batch of later-era chassis and variants for dipping into the Jihad and beyond.
As for miniatures, currently the only non-'Mech minis available for retail are Elemental Battle Armor points, and Shilone aerospace fighters. However, the Mercenaries KS brings the Visigoth aerospace fighter, Inner Sphere Standard Battle Armor, and a glut of combat vehicles of all shapes and sizes. You can wait for them to hit retail next year, or you can get them a few months early if you sign on as a late backer through BackerKit.
