Those are awesome colours, I love warm shades a lot. I like how you made the pencil lines really subtle, they don't stand out too much but just enough to give an impression of some sort of underlying structure in the drawing. I can't tell if the wider outlines are pencil strokes or added digitally but it's a good way to make the foreground stand out from the background.
The only things I could see improving are the glasses and the tail. Since glasses are normally just transparent, all of that white you used it not necessary. It could have been really subtle white (near transparent) and worked even better (maybe just use stronger white for actual highlights though). The tail could be fluffier; you could have defined the fur more with more contrasty brush strokes, but it's a minor thing since otherwise it's a great piece. I hope you don't mind critique... I like analysing artworks but I won't waste my time you're not interested.
Those are very good points you brought up. I highlighted the glasses way too much and tail could have truly been fluffier, since now it looks kinda too smooth and flat. I'll take these things into account next time!
And yes, the character's thick outline is made wholly traditionally . I try to avoid adding digital lines to traditional ones, because it doesn't always look natural.
If you still feel like giving critique about anything, you're free to go all on!
Oh, good to know. You already have a really good grasp on most of the things that a lot of people typically struggle with (composition, colour theory, lighting, proportions, stylisation, generalisations etc), so I'd be just nitpicking on the small things.