We have sailed on the Pride (similar to the Legend) and the Epic (around Europe).
There's a reason the cost is lower... and I am typically more loyal to Carnival than NCL.
I know the Epic is a very controversial ship, it was our first NCL cruise, and I absolutely loved it. The walls are kinda funky, but we were on the ship after a summer in Paris, and the amount of storage was truly incredible. I was able to stick away all the stuff we didn't need, but needed in Paris, and never felt like I was walking over a summer's accumulation of stuff that my teenager acquired.
The bathrooms are kind of weird, but I didn't think it felt exposed and really didn't have a complaint. Yes the sink is a little small and it's in a weird place, but it really didn't both me at all. The split bathroom really become not-weird very quickly and there's a curtain if you're really weirded out.
The food was excellent, we did all of the specialty dining and everything was outstanding. The circus show was so fun, my kiddo loved it so much we did it a second time. It was our first time doing the freestyle dining, and I really did love it, and once I realized we could request the same service team it was even better.
We were on the pride several years ago, and it's a small ship that feels like a small ship. The Epic is definitely much bigger (but smaller than like the escape, the joy, etc), in some 25+ cruises the only ship I've ever been seasick in was the Pride. The Pride was a nice enough ship, being smaller I think our dining crew and room stewards got to know us better, so that was great, but I think the teams on the Epic were also as great.
There were way more outside spaces on the Epic, I loved the top deck where there was some seating that was away from all the hubbub, and was so comfortable and restful. The Legend is much much older than the Epic, but both have been around for a while too. If I had the option, I would do the Epic hands down, I would probably stay on land if given the only option of a Spirit class ship, unless it was going somewhere I really, really, really wanted to go.