Appears quite reasonable to me, from as much as can be told. Also us hoofcare professionals are much more comfortable in the cold than working in the heat... so long as we can keep from getting a chill in the back!
Great that your horse has developed such hard, dry feet. Don't have much experience of snow where I'm from, so surprised to hear it dries them out!
I'll just point out what I see - green lines indicate where it appears the hoof *should* be if healthy, red lines indicate what appears wrong, blue lines show approx how I'd be trimming to facilitate growth of healthier form. *Pics/angles aren't the best for accuracy either, so take it as a rough idea only.
That back right looks like it has a 'broken back' hoof/pastern angle, seems this is likely due to stretched toes & 'under run' heels - they appear a bit longish but crushed forward. Hard to really tell with only that sole angle too. Possibly the heels could come down a smidge more, but if they're as run forward as it seems & it's not appropriate to lower them, 'bevelling' the heels at the ground surface will start to bring the bearing surface back and allow them to grow more upright. Ensuring the quarters are kept back to sole level, 'scooped' in relation to heel & toe, if/as necessary will be helpful, for the heels & also to relieve the excess stress which is causing the quarter flares. As will be keeping those bars down.
I'd bevel the walls from just inside where they 'should' be, such as it appears the farrier may have indeed done - hard to tell with those angles, so drew on your pics to point it out. This goes for both stretched toes and quarters.
Again hard to be accurate with that angle, but it does appear that front foot is a little 'clubby'. This just means that it's higher heeled than would be 'ideal' and often this just happens to one front foot - the other may be flatter. Also it's a matter of degrees and this doesn't look like anything at all major. *While I describe it as higher than 'ideal' that's not at all to say it 'should' be just cut down to match the other. It is usually a body/injury/postural thing & may well be 'right' for that particular horse. Whether that's the case or not, I think if it's going to change, it needs to do so with the help of a bodyworker or such, and done gradually. Too many ifs, buts maybes to go into there & couldn't say what may be best over the net anyway. So I'll just assume the heel height isn't/can't be changed.
So, as per the red line, this foot appears to have a bit of a 'broken forward' h/p angle due to the high heels. This can potentially be problematic due to the way the joints sit together and also that it means the toe of P3 will be pointing into the ground more and the rear of the foot may get too little stimulation/ground contact to be strong & prevent contraction. Protecting the toe sole and using a 'frog support' foam wedge or such, to give more support & stimulation to the recessed frog may therefore be helpful.
I would be careful to keep the toes backed/bevelled, well, to keep extra leverage forces from stretching/flaring them, and whether or not the heels need to remain high(in a 'clubby' or otherwise foot), IME the extra length shouldn't be carried through the quarters, so they need to be 'scooped' if/as necessary to keep them at sole level.