It looks doable but pretty packed out and physically tiring, also seems like lots of time on the road vs the stops. For me it would also be too many one-night stands in hotel after hotel. But it's really up to you. If you decide to forego Bromo, or if one of the volcanoes around it decides to start erupting so they close off access during the time period you're there, then putting the extra time in Surabaya is not a bad idea in order to avoid messing up your subsequent prearranged itinerary. I am baffled why Surabaya gets short shrifted (or a bad rap) in guidebooks. I had planned Surabaya just as a transport junction but liked it enough that I decided to stay a couple of days. The Sampoerna factory (and cafe) is great, as is the free tour around Old Surabaya they sponsor. I also enjoyed the Zoo (and I usually avoid most Asian zoos like the plague)--good place to see Komodo dragons and interact with the friendly Surabaya natives. I stayed at the Mercure Surabaya on Jalan Raya Damo and thought it good value for money. (Their food was good and so was their spa/massage).

I have stayed at the Phoenix Hotel in Yogya and liked it a lot. Great breakfast, good spa, though a bit pricey. The rooms are not huge but are very comfortable and the ambience and service is nice. I don't know the Rumah hotels. I also think the Manohara at Borobudur is a good choice due to convenience. It's clean and comfortable enough and the grounds are nice, but definitely not anything close to luxury and I can't recommend the food (but elsewhere in the village are other options).

Bali for 6-7 nights in two different locations (one of them Ubud) is perfect. So keep that part.