Well, there's a lot of nice colors, but what does all this mean? Basically, you have to go in this color order: green, orange, light blue, blue, dark blue, red. But hey, use your head a bit, it's not because you haven't finished the greens that it's forbidden to do the ones in oranges.
All the same, I advise you to have finished the greens and oranges before going to the shades of blue. Rendered in shades of blue, I put more or less the priority of research to place. But hey, I advise you to have finished the light blues before doing the dark blues. For the normal blues, it is especially for the final research to make effective sales sessions.
An important point about buying points: You can buy a few points at the beginning, it doesn't cost much, but quickly, the price will rise. After about ten points bought, I advise you to build up the philosophy before buying more. Normally, the purchase of points will be done mostly when you will be in blue tones. I calculated the whole thing so that the green and orange colours will arrive with the right amount of research when you are at the beginning of the Marquis row.