I can't make do without getting bottom surgery either, so I totally get where you're coming from, however I'm satisfied enough with what the meta procedure can offer. But, in terms of future improvements of bottom surgery options, from what I've heard around, there's quite some focus on improving meta so that it will give a bigger result. I heard about a new method that extends the cl*t by somehow "pulling forward" the internal parts of it, which can make it even a couple of inches longer in some cases (but largely depends on original size and other things too). One issue I've heard coming with it is risk of losing ability to get natural erections though. From what I've heard one or few surgeons have started using that technique in Iran (or another country in that area) and it looks to me like that, or something similar, could be more available on the market in a not too far distant future. The method is called "Extensive Metoidioplasty". I have a link to a study, but not sure if that's okay for me to post, cause it does contain nsfw pictures.
Other than that, I've also heard about lab-grown penises and 3D-printing, but that those are not as far developed yet. Oh, and I've heard of some having gotten a type of phalloplasty where the outer labia have been used for the phallus as/instead of a graft. I've only seen one result online and it looked really good, and seemingly that method has fewer complications that are associated with the graft cause of using tissue from the same area and not further away on the body/different type of skin tissue, but that method I know very little about. But that could quite likely become a more available option in a not too distant future as well.
So, I think realistic expectations are improvements on the already established surgery option of phallo and meta, and that 3D-printing and lab-grown penises will take much longer to become developed enough to be properly implemented into practice. But of course I'm no scientist and can only speculate.