Personally, I would not recommend MMs for beginners. They are not rally just summon and forget, you have to maintain an awareness of their health/buffs, resummoning them, sometimes often depending on what you're fighting.
For the same reason, I would not recommend support classes for beginners, which generally require situational awareness of your team, who'd fighting what and where, their health and/or buff status.
Granted some folks thrive in chaos. My first character in Legacy was a Kin/Arch Defender. 🙂 I tend to play Support characters myself, love buffing myself or the team while debuffing the enemies.
I'd recommend straight-up melee of ranged to get your feet wet. Brutes for melee are a relatively safe bet especially at lower levels, Blasters or Corruptors for ranged.