Horses:
70-300m lens at 70mm
f4
1.60sec
ISO 2800
Thoughts;
1) You've got the eye looking at you and appears to be in-focus; eyes in focus of the primary subject (in cases where you've more than one) is key in wildlife photography and a very hard "guideline" to not use. That the horse is looking right at you is a great bonus for this shot, there's even a nice highlight spot in the eye so all good there! The ears pricked up is a good bonus for equines, its an oft looked for element by horsey people so good points there.
You've composed generally well, the post at the bottom is annoying, but at the same time you can't really remove it without losing the mouth on the other horse in the background - although you could close crop around the single key horse if you wished.
Settings wise its gone well, f4 is a decent aperture for a horse considering how thick their heads are.
1/60sec is a risky shutter speed for this, at that speed you're running a higher risk of motion blur from the subjects motions or wind blowing the hair. That said it doesn't seem to be a problem here so looks like you caught a nice calm moment. I'd probably have wanted to be faster on the shutter speed if shooting the horses in general, but for a calm moment these settings have served you well.
Sharpness might be improved, but I've a feeling part of what we are seeing is that you've maybe resized and not sharpened both before and after resizing (resizing reduces sharpness so its always best to do a second run of sharpening after resizing before uploading to the net.
Two Bee shots
shot 1
lens 70-300mm at 300mm
f5.6
1/800sec
ISO 400
shot 2
lens 70-300mm at 300mm
f5.6
1/1000sec
ISO 400
This is hard photography you have here, the colours and exposures look good and solid, but your challenging yourself a lot here to get this kind of shot. A bee is a tiny subject that moves fast and their wings beat at an insane rate so getting a clear sharp shot (even with wings blurred) is tricky. It looks like you are on the right path though, appears that you caught both near flowers and tpyically for this you want to base yourself near a popular flower and let the bees come to you rather than chase them around the field.
Otherwise single point AF and a lot of practice is what you need. Sometimes you might find it easier to pre-focus (focus the lens ready for the shot) before and then let the bee move into the point of focus and then hit the shutter button (ergo use manual focusing). This speeds things up since you're not waiting for the AF to get a lock you're using your own eyes and the fast shutter on the DSLR to let it capture the moment. It's still darn tricky and this is one area where a burst of a few shots is very helpful (sometimes you might pre-empt the moment and shoot just a little early in the hope a latter frame captures THE moment).
Purple Flower shot
70-300mm lens at 220mm
f5
1/500sec
ISO 1000
I like this shot. It looks sharp (even after resizing) and the bright vibrant colours work well with the more cold and muted background. Overall I think this is one of your stronger shots; compositionally I've no strong feelings - I like it that much I can say but I can't see any clear ways to improve.
Settings wise you could probably have dropped a fair chunk of the shutter speed and thus used a lower ISO (or a slightly smaller aperture - bigger f number - but considering what you already have I don't see a need for increasing the depth of field in this shot). At 220mm the rule of thumb for hand holding (1/focal length of lens) would leave you at 1/200sec and getting a sharp shot without handshake blur (according to theory - different people and oft different gear will vary this value - some will be faster and some slower). If you were tripod mounted you could have gone slower still (but don't go too slow as otherwise even light wind or you moving/breathing nearby will give you subject motion blur.