Frankly, in gigantic galaxies, alliance wins seem virtually impossible. The amount of space allows empires to become extremely independent of one another. Because of the way I run my empire, I don't go picking fights, and I tend to build a research heavy set up, so in one game where I put a LOT of effort into trying for an Alliance win, I actually ran out of technology to research and ended up in a Tech win by default.
I play an ethical society, but I do make a concerted effort to remain friendly with the evil societies, and tend to succeed. In my last Tech win, I was a fairly median empire in terms of military strength, in a VERY distant 3rd behind the Iconians and Torians, but absolutely rock solid on research and influence, having taken a number of worlds from the Altarians, Torians, Yor and Iconians due to incredible influence strength within my border. I had about 10% of the galaxy under control and all the evil races were down. The Drengin had an alignment reversal hit (talk about some funny dialogue happening..."Don't mind how we look, we really love everyone"

), the Kvorx went down hard to the Iconians (#1 military by a margin of 4 to 1 over the pack), and the Yor never seemed to get it together. Military action just didn't make sense for me. The Torians (#2 Military) and the Iconians would have ripped me six ways to Sunday. I had aligned with the Drath and Iconians (despite relative lack of strength and the "We know what you're doing" because I was building up my border fleet to counter a possible Kvorx invasion when the Iconians flattened them).
Really, if I can't get into a major war with a buncha evil races, I've got little option but to punt for a Tech win. Sad because the treaty monitor showed blue lines all over the place for them...