So there's now a new system for upgrading suns. Each sun/seed has a maximum power, and players can upgrade up to that level. So some suns are level one and are limited to that. Others can go up to level three, making them high-cost and high-value bases. Also, the double-power stars have been removed. I think they ultimately confused things, and their original purpose (performance boosting) isn't so critical anymore. So now double-power suns just produce two stars at a time.
The new upgrade system called for a new way of displaying the different potential levels. I scaled up the suns when they got upgraded, and I put faded rings around suns to indicate when they could be upgraded further. I'm not entirely satisfied with that interface yet, but here's a screenshot of some new upgraded suns: