The painting is really good mate. As someone who had it pointed it out to me a long time ago, the only noticeable refinement I can think of it is sanding/filing away the sprue nibs completely. Citadel paint is so thick you don't even need to sand afterwards, but I still use a bit of P400, 800 or even 1000+ anyway.
They're tricky to find, but I hav some of these and they are really some of the best files I've ever used.
Only around £10-20 for a set of 10, but get as many as you can (some of them are 5x, 6x and other random quantities that isn't necesarily reflected in the price).
The round, half moon (use both sides), and triangular profile ones are especially great.
Needle files, normal style, NOT diamond (those are more course and for metal, and slightly more expensive) or much bigger wood/plastic working ones.
You can also do fine with a good scalpel, I use a combination of Swann Morton but also X-acto style blades. Swann Morton Retractaway blue handle is comfortable and safer to leave around and on the table while you work. I use it for almost all of my sign work and media conversion. A no.3 handle is also fine (and lighter but you're more likely to have have accidents).
https://www.amazon.co.uk/2806-Swann-Mor ... B007OX8PVMDon't forget a pack (or entire box) of 10A blades. These are EXTREMELY SHARP i.e. they will instantly cut you deep if you aren't careful. Surgical grade.
Citadel have a ridiculously overpriced deburring tool (more for mould lines which are fairly well hidden on citadel models) but you are fine with a scalpel. Filing is better as you won't accidentally remove parts of the model.
I usually do a bit of both.
Edit: This set of 6 stocked by amazon are 3mm wide, which seems to be right. Set of only 6 but the profiles are some of the ones I actually use the most.
https://www.amazon.co.uk/Yato-yt-6160-N ... 009SFN53M/Just under £8, really good for the money. They come in a little pouch.
Edit: Found the set of ten, just 9 quid including delivery
https://www.ebay.co.uk/itm/175439645250Massively recommend for anyone here.