lol, I'm the same with these birds
I brought my camera with me today to try to get out at lunchtime too, we've got a pair of buzzards which seem to hover around our building, so am hoping to see them today.
wrt to these 2, the second one is much sharper, maybe a little play with the levels and a small unsharp mask would bring out the detail a treat.
The first one, I think it what I spent too much time doing, and that is trying
too hard to get the shot, where actually he is *just* really out of reach of the lens. ie, you're making the lens work too hard.
I suspect the top one is a fairly heavy crop again, and again a bit of PP should bring him back a bit.
I've found that I'm not going for the shots where he is over 100ft (ish) away from me, and just try to have some patience and wait for him to circle down to 50-100ft level. I'm thinking that the second shot was when he was much lower as he is much sharper and the lens hasn't stretched.
What lens are you using? the second says it was at 323mm? (no exif on the first).