The sorc route is fantastic, and extremely fun. It is also infinitely variable to play: you CAN target any route in the game with the right route setup.
Whilst Iamsmart sees the route as weak, I find it incredibly strong for the reason that Iron Golems have health. They may not look it in the stats but those guys have enough health to survive strikers / assassins / RPGs and a whole lot more! They are the ultimate in lethal flak for your sorcs OR dragons, depends what you are after.
I personally love dragons, because their damage output is incredible. If you catch offline solos, you will demolish them. I was repeatedly attacking at 130-180% of me when I played solo dragon and frequently winning against SOs, Puppets and Thug players.
If you want to save the cash, FFX proved that playing Golems + Sorcs alone is incredibly fruitful, with the golems to destroy the flak and the sorcs to fire on the leftovers.
In terms of ratios, I say buy up to suit your needs! My ratios were constantly changing to suit the enemy. If you want to bounty hunt a TL, buy sirens. If you want to kill an SO player, buy dragons. If you want to destroy a PoM, buy lots of sorcs.
If no dragons and you want to make the Golem + Sorc combo work, there's a simple equation you'll need, to figure out how many golems to send to kill the flak before the sorcs fire:
Total number of enemy troops / 4 = Golems required to kill all the enemy flak.
Warning though doesn't remove all the basics, so watch out for that
But works on the whole and lets your Sorcs annihilate any leftovers.
The only routes I would avoid attacking (if using dragons) are RPGs, Strikers, CWs and mass Harriers. The route is better suited to HD on the whole. However, if you scrap the dragons and concentrate on Sorcs, you can beef your HD and destroy Strikers and Robos, just so long as you remove the flak first!!!