The Lakland skyline is just about the ultimate ($) hollowbody. Or,for about half the price of that,,i can't say enough good things about the Italia Rimini.
I found the Epi JC to be very uncomfortable,plus I prefer 2 pickup basses. I can't comment on the belvedere,never checked one out. In addition to the Rimini,Italia makes a number of really cool HB basses,and they seem to be made well. I also just sold a Danelectro Hodad bass which had a great sound,but i think the Italia is even better. I've owned several other hb bases over the years,and the lakland and the italia nail it for me. You will probably have to do a little work (setup,frets) on the Italia,tho.
Also,if you find your 4003 uncomfortable and heavy,but like it,you should consider a 4004,they are usually lighter and way better ergonomics/feel.
+1 I bought a JC two weeks ago and played it for a week but just couldn't get use to the dimensions. To me very uncomfortable. Tone wise, I was impressed - especially with a fuzz and a lot of OD. Great raw sound. Returned it minus shipping.
Haven't played the Skyline but it looks sweet. A lot of money for whats on the market.
