sorry but no:)
mostly because with 2 high poly lods out of 4 lods, it'd mean to have an unbalanced LODs succession.
BTW, it's really a nice start, but I give you a suggestion for when you work on blubby models:
Consider the main body of the ship. Look at the ventral area: it has a very wide angle, it's almost flat. You don't need more than..say 4 edges on the trasversal section for this area.
The borders instead have a narrow angle, they are more curved, and need (proportionally) more edges. 6 Edges should be enough.
That's a total of 20 edges for the trasversal section. Want to oversmooth? go for 24 if your pcount isn't already too high.
This mean to not only deform a sphere or a rounded cylinder, but also to control the edge density, smoothing only where needed.
I don't know how many edges you used (but to have 20 k you probably used a lot of them)
It also seem from your pic that the longitude of the various elements is more rounded (proportionally) than the latitude (the number of trasversal elements).
But I may be wrong because it's hard to judge a rounded model with smooth shadings from a perspective view.
