I was curious if there were any group hiking tour companies that go through the Highlands that are similar to the length of the Tour Du Mont Blanc?
The Cape Wrath Trail ,or the Scotish National Trail are the two biggies.
Whether theres groups ,I can not say.
The very popular West Highland Way enevitably has bag carriage and must have guided too .
You could have a look at this company. They would appear to offer bespoke tours so are likely to be able to offer you what you want
I did a 5 day self guided tour in the Highlands which included part of the West Highland Way with HF Holidays. They do fully guided tours of the WHW as well as other hikes. Highly recommend them. https://www.hfholidays.co.uk/