Re the bar trimming, yes, looks like they could do with a bit & sounds like you need to sharpen your knives! Yes, hooves can get very hard in the dry, but after a soak or rain, if your knife won't cut...assuming you're not a real weakling
your knife's not likely very good.
IMO understand what lies beneath & the principles that make a certain hoof form more or less 'ideal', but remember that this 'ideal' is an average & that all horses are individuals & there are always ifs, buts, maybes.
Your horse's heels/frogs look weak & contracted(they don't need to 'fill in' but open up), and considering this, while I can't see hoof pastern angle or anything else to help gauge(which are also necessary factors), her heels may be about ideal for her right now. If/when her caudal foot becomes stronger, the heel height may drop because she's using them more, not 'tippy toeing'. I'd be inclined to use dome or frog support pads in the boots with this horse, to prevent peripheral loading of such a concave looking hoof, and to provide *comfortable* stimulation to the frog/DC.
How old is she again? If she's quite mature & always had contracted heels, it may not change much if any.