Hello and welcome, Gandalf the Grey! I think some of your highlighting work is very good (especially Gandalf and Bofur) and your choice of colours are interesting and deviate slightly from the 'official' colour schemes, which is a brave move that is well worth it
However, I would suggest you put a bit more effort into your basing. Just covering the base in static grass and adding some pebbles makes them look a bit rushed and can distract from the painting. I suggest covering the bases with sand, adding a few patches of static grass and only one or two pebbles - less is more! Also, you may want to paint the stones a different colour to make them look more natural - i suggest painting them black, then drybrushing with grey
Another thing that's worth putting extra effort into is the faces. Unfortunately, they're arguably the hardest part of a model and if you don't have steady hands or weak eyesight they can be very challenging! I suggest you try not to rush them and to give them highlights just as you would a piece of clothing! try thinning your paints so you don't mask any of the detailing; the dwarves faces are notoriously small!
don't be dishearted, I think your models are pretty good for first figured and much better than my first models way back then. Just keep trying new things and experiment: the models should please you first and foremost! Excuse the lengthy reply!