This board I probably open Masq/Silver looking to pick up a witch/YW depending on my draws and then transition into a Wharf/Village engine. I'll probably start favoring FG over silver/gold after I get a wharf or two. Though if I had picked up YW over witch, maybe I just get a tunnel midgame to give myself a steady supply of Gold.
As for general strategy, people love tunnel way more than they should. Yeah, there are a lot of decent enablers, but only a few are really good. And oasis is not one of the really good ones. Best enablers off the top of my head are warehouse, young witch, and embassy. The problem is that the tunnel takes up a card slot and then if you happen to discard it, you have to wait an entire shuffle to actually see that Gold. Oh and tunnel continues to take up a card slot for the rest of the game. Warehouse and embassy both cycle your deck like crazy. So you don't have to wait long to see that Gold come around. They also don't care about junk very much at all. Young Witch takes a different route. The cycling isn't as good, and it's terminal so you can't stack it like warehouse. But the curses slow down the game a lot so you'll see those early golds a lot. Also it's hard to get many gold anyway in a curse game. Plus it's going to be a junky game anyway the card slot from a tunnel or two isn't so bad.
