This app was mentioned in 2 comments, with an average of 1.00 upvote
I usually play on a 3 player group but sometimes it grows up to 5.
5 players make bases score way too fast thus we are thinking about adding +7 break points on every base on the board. We haven't tested it yet, it just came up from brainstorming.
We've tried playing with more than two factions... it didn't work that well to us. Perhaps it could work for you.
If anyone in your playing group has an android phone they can download and app to randomize decks. Quite handy IMO.
As for tips... remember that boundaries for what a card does are very explicit. If no boundaries are written there are actually no bounds for that card.
Not mine but we use it
https://play.google.com/store/apps/details?id=com.ulusol.smashuprandomizer