According to the leaked Hasbro database listing, there was only 4 Decepticons... and all the rest were Autobots and Dinobots.

The Decepticons on the database listing were - Galvatron, Lockdown, Stinger, Rally Car (Vehicon).

But it isn't the first time that they are producing a lot more Autobots than Decepticon toys for the Movies.
For the third movie...
- mainline (Deluxe, Voyager, Leader), there were 25 Autobot toys verses 8 Decepticon toys. That's a ratio of 3 to 1, or 75% were Autobots.
- Human Alliance, there were 14 Autobot toys verses 3 Decepticon toys. That's almost 5 to 1.
- Cyberverse (Legion, CMDR, Action sets), there were 22 Autobot toys verses 11 Decepticon toys. A ratio of 2 to 1.
- Gimmick toys, there were 25 Autobot toys verses 9 Decepticon toys. Almost 4 to 1.
- Hasbro Exclusives, there were about 46 Autobot toys verses about 12 Decepticons. Again, almost 4 to 1.

That totals about 132 Autobot toys verses about 43 Decepticon toys in the 6-8 months of the TF3 toyline... about 75% are Autobots, 25% Decepticons.

A massive imbalance during TF3 despite having a bigger cast of Decepticons than TF1 & TF2... but perhaps retailers demanded more good-guy toys, if kids and parents were not buying/receiving villain toys as gifts.

I think this fourth movie is going to be even more out of balance, as we appear to only have 4 Decepticon characters, and very few toys so far known (or leaked).