Hi Daisy!
I have climbed Mt Blanc 3 times and by 3 different routes. It's quite nice and doable especially the 2 normal routes (Gouter route and 3 MtBlanc route, these can be combined for a nice traverse). A guide might be useful for the 3 Mt Blanc route and all more technical routes.
It is busy from june to september, normally it can rain a week and then be good for the next, so everybody will head up simultaneously and if you do not have hut reservations you might be in trouble!
When are you going? I have guided people up there...
It might be busy up there:

(From my 2nd climb, Gouter route up)
This was the view from the summit the last time:

and this towards the Monte Rosa:

Thanks for the Scotland pics, I love Scotland in winter, is that Stob Coire nan Lochan?