What I find is, if you’re feeling that none of the names you think of are quite right, it may mean that you need to go back to the basics and really think about what you want to convey. First step for me is to consider how personal the name should be. On a capital ship, the name must be both relatable and pronounceable for a whole crew, while a one- or two-person freighter could be called whatever the captain wants. For that reason, in most cases I would recommend a more general name for a large ship, such as the Resolute or the Endurance. Generally, any cool-sounding noun or adjective can work. With a smaller, closer-knit fighting force like the Rebellion, you do see more contextual names, such as the Raddus and the Urjani.
With smaller, privately owned ships, there are tons of things you can do. I believe that, whenever possible, it is best to name your ship in some significant way. If the name has real meaning and relevance to the owners, it won’t sound stupid. I like to look at whether a reference to the captain’s planet or culture would be appropriate; for example, I have a light freighter called the Cin Vhetin (”clean slate” in Mando’a), referencing both the ship’s background and the fact that the captain is Mandalorian. You can find plenty of these general types of names, even if they aren’t entirely personal, like the Coronet and the Chandrila Skies. Of course, there are other ways to give a name significance. Think about what it means to the captain, how they came to own it, what they’re going to use it for, stuff like that.
If a personalized name just doesn’t fit with the circumstances, try looking at existing ships for inspiration. Here is the Wookieepedia category for starships by affiliation. You can look through the ships owned by different factions, which is helpful because different factions tend to have certain styles when naming their ships that you may or may not want to adhere to. Another good starting point would be a name generator like this one, though you will probably find that you have to modify or play off of the names you get.
Just keep in mind that you will probably be far more critical of any name you come up with than your readers. Ask yourself whether you would spare it a second glance (in a negative way) if you read it in a book. And if you really aren’t sure, run it by someone! I can certainly give feedback if you ever like.
Hope that helps!
~ Jacen