I love how Ultra Plants allow us to get otherwise tough to get items in the game! Motes being tough? Farm for Ultra Plants! A wonderful feature! So wonderful I want more.
I would propose two new Ultra seeds inspired by the Ultra Helephant ears.
1) Evil Ultra Peas These drops exclusively from Evil Snow Peas and drop the same things most Ultra Plants drop (with a mote of severity in it's reagents pool). They mostly drop Evil Snow Peas, occasionally reseed and rarely at elder harvest can drop 1 Evil Magma Peas seed. I think it's about time to give people a real reason to grow Evil Snow Peas other than when they are starting, Convoluting the process of getting EMPs to make it a rare drop from a rare drop is very in keeping with other plants, like Deadly Helephant ears.
2) Ultra Couch Potatoes These, similarly to above, would not drop from their crowns shop representitive, but instead from the Red and Golden Couch Potato variants at a low droprate. They would also have standard Ultra Seed drops with a mid-tier mega snack like Sun Fruit at mature and may drop regular Couch Potatoes Seeds and/or a Mote of Transport (because I think I'm hilarious!) at it's elder harvest. The goal with this being to give new players a reason to actually grow their Red and Golden Couch Potatoes they get from quest rewards, like in Azteca.
Long story short - Let's get Ultra Peas and Ultra Potatoes to give new gardeners a way to these crowns seeds without hours of farming mobs just for one seed. Let's also reward growing otherwise "useless" seeds that players are frequently exposed to. Maybe we can have some fun designing them along the way...