I have played most of the Haydn sonatas at various times. By far the best is the last one , No 52, could have been by Beethoven and is contemporary with Beethovens early sonatas. Many of the early ones are relatively trivial. You have to get to no 23 in F and also 29 (also in F) to get a decent one. I particularly like no 23. otherwise its the last dozen or so like the 49 you are doing and also no 50 (Known as the English sonata) which give satisfaction
I’ve just discovered Haydn and am thoroughly enjoying it - playing the XVI 49 E flat major sonata and it’s such a joy to play!
I’m still relatively new to Haydn (have only been playing piano for about 6 years and there’s a lot to get through!) but definitely enjoying it - something about the style just works for me - I was prompted by my teacher to get started with an earlier G major sonata which was relatively simple but enough to get me interested - and then went on to sight read through most of the sonatas up to 49 which I’ve settled on for now and hope to play for a little concert in a month’s time. I so get the Beethoven connection with the later ones - love it!