There's an implicit assumption here that you can't go for multiple types of VP in the same game. Let me remove this burden from you.
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A Vineyards deck is easily going to be able to pick up both Colonies and Vineyards if it's any good.
This seems a bit doubtful. Yes, it should not be that hard to ramp up a Vineyard engine to hit $11 or $22 ... but in the process of stocking your Vineyards up you will have left quite a few piles depleted. Getting Vineyards running often means that you present a nice easy three pile before you can build out to a Plat or two for colonies. This presents as an interesting problem - do you continue to overbuild your engine (which you want to be able to hold off at least 9 stop cards) or do you skip the Pot & greens to get a few colonies ... and enough +buy/gains to 3-pile before Vineyards can hit serious buying power/point totals?
Likewise, if you are using gains without +buy and where your gained cards don't generate (much) cash; it can take a pretty long time to build back to $11. Something like Village/Smithy/Iw/Wwell can go a long ways toward bulking up Vineyards, but until you want to start Iw'ing for cash, you have a hard time hitting $11. Vineyards can actually be a setup where you either rush it or slog out ... without touching the colonies.
As far as the other scaling VP:
Dukes are generally a poor choice. Outside of 3er or higher, they max out at 8. Thus all Dukes/Duchies tops off at 88 points. That is a hard win against provinces/estates, but relatively easy to beat with Col/Prov.
Fairgrounds can be suprisingly competitive given the strength you can build into engines in colony games. Sure there are Bm games, but don't overlook Ruins/Shelters/Travellers/Prizes. Basic colony setup is 19 cards (4 Green, 4 Treasures, Curse, 10 kingdom); 20 happens a lot of ways (Potion, Yw, Hermit, Urchin) so you can easily get to where Fairgrounds become cheap colonies if your engine can support it. Also of note, these tend to be really good when you need to dance down green cards if you cannot safely end it on colonies.
Similarly, Gardens are often not a bad thing to nab over duchies if you start green dancing down that low. Say you end up with 3 Col, 3 Prov, 6 treasures, attack, trasher, +buy and some draw combo that can draw all of that (say 4 Village, 4 Smithy, 2 lab). That is 25 cards and a very lean deck; colony games make a lot of fat deck engines actually viable. Keeping your starting estates (say with Loan as your only trasher) or even all your starting cards (no trashing) is quite doable. 4 VP gardens should be expected in any really close Col/Engine race.
The other big thing to remember about colony games and Alt-VP is that you often get a lot of setups that are dangerously close to a 3-pile. Colonies encourage deep, reliable engines. Iw/Worker's village/Smithy should likely build out to an engine for a Colony board ... but when you both try that you can find yourself looking at an easy 3-pile. This is particularly true if you have curses flowing. Alt-VP can be very handy to eke out a win when piling. Being able to Iw a few points off Gardens can be huge if you are stealing a win after the other guy first buys province.