Had a gander at those tracks you sent over this morning. A good listen -- well done on the
music!

Anyway...
First things first, based on the mastered mix you originally had as
an example from the same engineer, I think you've got pretty much what I'd have expected
you'd get, if you see what I mean. In other words, your mix is very much in the same
ballpark as that one, give or take a bit of top-octave air, some extra loudness, and a
different choice of bass instrument.
However, comparing with the 'Trip To
Glenfinnan' reference, I can see what you mean when you mention the difference in
instrument definition and the sense that the lead instruments in the mix you have seem a
bit muddy at the moment. However, the good news is that I don't think this would be too
tough for the engineer to fix for you with a few mix revisions.
The main issue
as I hear it is actually the drums, in that these feel closer, clearer, and (particularly)
more transient than the rest of the ensemble, such that they make the other instruments
inevitably feel a bit muffled by comparison, no matter what you may try to do at the
mastering stage. I'd ask the engineer to round the drums off a bit, perhaps pull them down
a dB or so, and maybe give them a touch more short reverb as well to push them back a
notch in the depth perspective -- although in the latter case it might actually be better
instead just to pull a bit of the ambience off the lead instruments if possible, as
they're a little too wet, I think, if you're after more of a 'Trip To Glenfinnan'
sound.
Other than that, the biggest issue for me is the overall mix tonality,
and although this is something you could tackle in mastering too, I think it'd be better
to bring this up with the mix engineer, because I reckon you'll get better results by
targeting specific channels than by processing the whole mix at once. Your current mixes
have quite a smoothly balanced spectrum, but if you want the slightly more rootsy and
forward sound that your reference track has, then I'd lean more heavily on the 500Hz-3kHz
region -- just mucking around with EQ on the 'RTHJ' track, for instance, I ended up with a
4dB boost at 1.5kHz with Q=0.6. The lower mid-range might also be thinned out a decibel or
two at around 200-300Hz. Both of these EQ moves apply more to the lead instruments and
guitars than to the bass or drums, though, I reckon.
One last thing to bear in
mind is that the layered/double-tracked fiddle textures you're using will almost
inevitably sound less 'present' and 'forward' than the single-instrument lines of 'Trip To
Glenfinnan', so if that's an important part of your band sound, then you have to be
realistic about your expectations in that regard. Although that reference track does layer
instruments, they're different instruments, which doesn't have nearly the same
homogenising and distancing effect as double-tracking and layering the same instrument.
So, overall, I'd say you're pretty close to where you want to be already, and
probably not more than a couple of rounds of revisions away from the kind of result you're
looking for.
(One further thing, though -- Syradale's vocal sound feels
inappropriate to me. It seems quite toppy and aggressive, which doesn't really do the rest
of the track any favours, I think. A less heavily processed sound would probably be more
in keeping with the rest of the production.)
Hope some of that makes sense!
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