Why not both?
Currently Engineering makes Guns, Mounts, Their Battle Rez, Special Ammo. Toys, and Cooldown bombs.
Why couldn’t you have all that on a Tech themed class as well? (It’s a little strange to me that the only class who can use all those powerful explosive ammos is Hunter)
Blizzard isn’t going to add a fully capable Healer, Damage, or Tank specialization to a Profession after all. Otherwise that Profession would be outright mandatory.