A dedicated industry alt is worth it only if you can do more stuff on it that generates your income than just manufacturing drones and ammo, like trading, blueprint research, invention and PI. If you’re building just T1 stuff, then option 1 is OK. But you probably want to build T2 drones at least, which requires few million SP of Science skills. And since you can’t build T2 stuff as an Alpha, then option 3 is out of the question. I would go with option 2, but first check with EVEMon how many SP you require to do invention and manufacturing you want - you might be having enough SP in redeeming queue after the latest event so you could apply them to the second character and there might not be a need to buy a MCT.