Is using gp on quasis/terraformers better? Should i get a transfusrr? Or get a dyson mission first?

Get your mission dyson first, its extremely beneficial in the lower ranks. As for buying QSEs and terraformers, don't worry about those. TO troop carriers show up later which will give you what you want. Reality transfusers would be useful to use on mission exotic or Dyson. But since you're asking about mission dyson you must have your mission exotic. Id recommend getting a hold of a planet with rings, adv ruins, or moons before you make it. Id say rings most of all in those. QSEs and reality transfusers also sell for a nice amount of CTP btw.

Earn your Exotic. Buy your Dyson.

Don't buy Terraformers, but do buy QSEs. I think I've gotten about 12 QSEs in my 250k kills. One thing people don't mention is that, while it is possible to auto-rank and NPC hunt as much as you want, it can take a huge amount of time. Unless you're willing to invest at least a couple hours a day into NPC hunting, you won't get many QSEs for quite some time. Just make sure you don't waste them; use them to make things like VM Icy planets that you can melt, or Gaias, things of that nature. Transfusers are good, but only use them on really good planets (Invincibles, or planets like the Gaias I mentioned). But yes, mission Dyson first.

If you plan to play for a long time, I would disagree and say buy your Exotic, buy two extra terraformers and a quasi to make it VM 15x all, then buy a transfuser for it. The earlier you get this planet, the better it will be for you in the long run. Either upgrade your worst planet or find a nice enemy planet with lots of tasty artifacts and use that. (Especially useful if you find something with upgraded planet buildings).

I'll agree with ODragon on getting the exotic as early as possible... I had mine completed as soon as the mission became available, and then upped it to the VM 15x and transfused it for large moons, and for the longest time, that planet put out more production hourly than over half of my others combined. I also bought the qse's right away for the mission Dyson, as well as Rift (waiting to find something worthy of rifting though). If you can afford it, it can be very beneficial and much faster to up your planets with GP, but definitely agree with above... Buy enough to get the mission planets, then transfuse only the very best ones you have.

While it would probably be better to not spend gp in terraformers, it really depends how much npcing you can/are willing to do.
20-25 levels of just npcs should be enough at your rank.
The amount of gp spent on terraformers, could cover most the cost of a rift.

I have only killed 1k npcs. Got 5 terraformers already. Want more...

ya i wish i had done that .. if u npc allot terraformers drop quite regularly