You're doing OK, but I'd be getting a professional at least every few months to help you with difficulties & keep you on track. While it's obvious the horse has improved in some ways - you have taken care of the cracks by the looks of things & they'll be grown out soon with any luck - there are some things that concern me.
Agree with luvs2, except (maybe, see below)for backing up toes & general wall length - I'd do a bit more of a mustang roll & keep on top of it every week or 2. Don't think they need backing up at all. I also don't agree that the walls are too long, except maybe at the quarters - looks to be less than 1/8" to me. Tho can't be really accurate with just these pix to go on, let alone not knowing the full story & being there to see for myself... so take whatever is suggested with a grain of salt....
He looks a little long & underslung in the heels in the earlier pics. This doesn't appear to have been improved - maybe even worse. IMO more heel and bar material could have come off in the beginning, certainly could now, and perhaps a heel bevel would be a good step in getting the heels further back.
I'm a little unsure of the pics, as I'm not sure which foot is which in some pix, but in the 7th & 8th November shots, it seems that the heels may actually be higher than in the beginning. But in the 11th & 12th shots it appears they're well short enough(??) Are 7-8 backs, 11-12 fronts perhaps?
Have you left them longer on purpose perhaps, to help him be comfortable on weak heels/digital cushions? I don't think they need to be that high anyway, if they still need to be high at all. The frog also looks possibly more contracted, which it wasn't in the June pix. This means he's likely to be still landing toe first with sensitive heels. Lowering them & using boots maybe with pads would be my preference, to get him using & building the back of his foot without making him uncomfortable. You need to do whatever you can to get him comfortably landing heel first. The 7th shot makes it look as if the inside heel is more forward than the outside too. The last pics make it look like his feet are different angles & not matching, which they appeared to be in the earlier pix.
In the last of the October shots - side on back foot shows that the foot has taken care of most of the excess quarter length itself - you just need to keep it rolled - but the rear of the quarter seems to be still a little too long & jammed. This may be from the high heels & if you're leaving them longer temporarily for comfort, you still need to relieve the quarters immediately in front of heel buttress. The bars also need to be brought down a bit more. As a rule, I treat them the same as the rest of the wall, keeping them close to sole level.
It appears the horse has rather shallow feet, at the front at least. *As a rule*(never say never) I don't think it's a good idea to pare the sole, certainly not routinely and especially not to the extent *it appears* you may have done, and especially not on a horse with shallow collateral grooves, which mean there is little sole depth under the coffin bone anyway. I believe the way to healthy feet is to *grow* a well connected, concave foot, not carve concavity into one which if flat, is not ready for it. As a rule, you should be able to exfoliate all that's necessary with a hoofpick rather than a knife.
I'm also concerned with the colour difference at the toe, which can be seen clearest in the 7th Nov shot. It appears this is stretched laminar material, or a 'lamellar wedge'. This would change my advice not to back up the foot further, as it's obviously seperated & stretched forward of where breakover should be. On that note, I'd be getting xrays & professional help too, before changing anything much.
Studying Pete Ramey's site & resources at Pete Ramey hoof care heals founder in horse’s navicular disease farrier
should give you a bit more understanding of the principles that effect my suggestions & concerns. I'd advise you find a *good* professional to come help you stay on track, even if it's only once every few months & you do the interim trims.