I haven't played with Triumph yet. Seems like it would pair very happily with Goons. Buy up a ton of stuff, use your last buy on Triumph, get nearly double the number of VPs you would normally get from buying stuff with Goons alone. If you've got enough money and buys, I'm assuming Triumph's +VP / gain will stack, though the payoff on just buying only Triumph isn't great. In a vacuum though, without extra buys and/or ways to gain additional stuff in a turn, I don't think Triumph is worth it. 2 points for <5>? I guess you could feed the Estate to a Temple or a Bishop.
The game I played with Conquest also had Catapult / Rocks and Tomb, so that turned out hilarious. I think I bought Conquest on its own once or twice. I went double Catapult and basically started launching treasures as often as I could. I got Rocks whenever I had the money for it. Once or twice I was able to Catapult a Rock, which gains me a Silver, then bought a Conquest for more VP than usual, that seemed fun. Even in a vacuum, Conquest has the same total cost as two Silvers, which is what it gives. It's harder to hit $6 in one turn than $3 over two turns, but you only have to spend 1 buy and you get VPs out of it, so your effort is somewhat rewarded. I might be happy to get Conquest over Gold once or twice?
I'd probably value Conquest more on boards with lower costing alt VP. Smoothing out my hands for more even slightly-above-average hands would be fun if I don't care as much for Provinces. Like ignoring Feodum or Gardens, which would be the obvious enablers imo, I think I could be happy to tunnel vision for Conquest over Gold on boards with Dukes or Silk Roads. I make it easier to get alt VP per hand, and I shore up the potential Province differences with minor amounts of VP from Conquest.