Attractive side lighting. The background is cluttered which takes attention away from the subject - don't be afraid to remove a leaf or two. A few minutes spent doing that will pay dividends in the resulting photos.

There isn't anything that you can call the 'correct' tonal value, it's all very subjective, so as long as it looks right and you're happy with it, then I'd say that's fine. Everyone will have their own preferred tone if they were to do their mono conversion so I wouldn't worry.
When I do mono conversions, several different settings can all look fine and are just that - different.
For example, you can push contrast harder in mono, and the sky here is a case in point. It can be darkened and made more contrasty. his would look good, but if it's not the 'mood' you want, then leave it as it is, as there's plenty of detail and texture there already.
there's good shapes and tones in the image which makes mono work well, and I prefer this over the colour one.

Keith

There are very good lead in lines from the fence and the footprints.
A stronger image would result in cropping the image from the top of the tree as that sky area adds nothing. This would also avoid the horizon being in the middle of the image. You could also darken the top part of the sky to give more gradation which would be visually appealing.

Nicely caught pose and the bits of snow on the animal add a nice visual touch.
This is low in contrast and a small tweak to levels or curves would sort this out to make the most of the image.

The main image is the boldest and strongest. It also has the most dram in terms of light on the subject. It would be better if the boat was closer in to the foreground as it's empty as it is. A good sky means a mono version should work well.
The second image says nothing, it's one of those images that just needs a caption to explain it. It also needs a slight clockwise rotation.
The third image makes good use of the foreground, though it would be better if the red building on the far left was cropped out (in camera or later) - the red lifebelts are ok, they don't distract like the building.

Just a trim off the right as the girl is very central and would benefit from being off centre, and there's a lot of black on the right - you don't need so much, and a little less would still provide the necessary mood and feel.
Having said that it's an appealing image.

Looks like some wholesale cloning to increase the aamount of sky. I don't see that we need so much sky, the interest is all in the land, and the mods with a bump in contrast have emphasised that.
If you wanted more sky, make a selection of it and use the transform tool on a new layer to stretch it.

It's a nice angle on the bird, especially as it has it's head turned sideways. The grass in the foreground would make a nice frame except for the fact it obscures parts of the bird, importantly part of it's beak. It would mean a lot of fiddly cloning and healing work to change this. You can't direct these creatures unfortunately

Well done for getting a decent close shot and keeping it sharp and detailed. Not easy in these situations. However, the fact that half the face is obscured doesn't make it so easy for the viewer to engage with the subject and it's hard to see the energy/emotion. I'm sure it means a lot more to you as you were there and you can remember the music, but for someone who wasn't there it looks more detached.
This wasn't meant to sound negative. It's clear you put some effort into this which is 80% of the battle, so look forward to the next opportunity.

I agree about the texture. The grouping is rather one sided, and the stem cuts diagonally across the image, so I'd rather see a neater arrangement. That said they're good flowers and if you shot them today they should still be fresh enough to have another crack tomorrow. Assuming you haven't already got a stash of different images of them ready to upload

There's a strong repeating pattern here which would translate well into mono image. The path leads the eye through the image well, but the eye needs something to be led to at the top of the image, be it a door, tree figure, etc, in order to hold the attention longer.

Well it would be a shame not to go for the reflection, as they aren't always so good. A tad less exposure would have kept some detail in the white feathers. The blacks and the dark areas of the reflection also look on the light side. Worth seeing what you can get out by revisisting the RAW file, and post as a mod.

Nice dappled lighting. A pity you've just cropped off the left hand edge of the building.

The horizon is very central. sometimes this works. However, here, try a crop from the top of the brightest part of the cloud. Not only will this balance the image more on the thirds, but the top third of sky can be lost without any detrimental effect.

Nicely captured pose, though the image is soft - focussing is critical when working at long focal lengths. If this is a crop from a larger image, again that may show up any small errors.
However, as I say, it's well timed. Cropping out the lump on the twig would remove a (small) distraction and make the bird less central, placing it on a third for a more pleasing composition.

It's good you've captured the reflection as such in the sand. However, the hotel is very central. It would work better vertically (and you can crop this to that effect). Also, there's your shadow visible in the bottom right, often an issue with low sun.

It's worth having a go at correcting the verticals - easy to get them slanting with such a wide lens.
I can see you've used the railing as a lead in line, but it also tends to draw my eye away from the rest of the image, so taking one with and one without is an idea for next time.

The elements in the image are nicely juxtaposed. It needs a bit of unsharp mask to crispen this up a bit. It would also look good in mono.

Well shot and posed, and the mono look is great, there's a nice wide range of tones there. It seems a shame I have to say that it would be better without the leaf by her right elbow, but it does look as though you'd be able to clone it out easily enough. I know it's easy to miss such things.
Nonetheless, a fine portrait.

Keith

The curve of the buildings is attractive, and the lighting across the image helps with the modelling.
I'd clone out the bright blob at the top left a it is a distraction. You could also try lightening the very centre of the image as the eye is led there by the line of buildings yet it's extremely difficult to make out detail there. With the camera used you were at the mercy of auto exposure, but you may be able to lift the darkness a little in Photoshop.
There is some noise evident so I guess it was a highish ISO, though it's not intrusive and looks like film grain.
Good beer from Prague