Recent set releases have conspired with some poor Standard environments to make me break that rule, and now here we are again with previews coming at us faster than Standard bans and I am just too excited to not start the brewing process
As for card advantage, look no further than Glimpse of Nature and Beast Whisperer and other cards that make super cheap creatures cantrip
In fact, while I don't have scientific data, just looking at the impact of flashback, I wouldn't be surprise to find that it is one of the most constructed-playable mechanics ever printed
Also most people don't run cards like Riftsweeper
What cards would you add to make it a fully powered up Upgraded, or bump it up to Optimized
Genku, Future Shaper The colors are excellent at flickering permanents, so look to trigger Genku, Future Shaper as many times as you can to benefit from making some neat tokens