Have been where you are now, twice. Both times we got lucky and the market went up dramatically as the area improved but we were seriously nervous about the £££.
House 1 - Tiny 2 bed terrace. Bought at the absolute outside of what we could afford with no room to extend. Stayed for 6 years and only moved when DC2 was on the way. Did some structural stuff [new roof, boiler, bits and pieces of wiring] but mostly decorative incl new bathroom and kitchen.
House 2 - our forever house. Lots of equity and a big redundancy payoff so invested £££ into what was a big fixer upper project. Total replumb, new boiler, re wiring, loft conversion, replaster etc. Put in the best of everything we could afford and tons of insulation for the future to keep running costs down.
Moved within 5 yrs. <facepalm> Usual reasons, schools, ageing parents, etc etc
You will spend [unless you both live the life of Sex and the City and never eat at home] a substantial amount of time in your kitchen, together and with friends and family.
You say "I don't want to spend that much and then move shortly after"? What circumstances might make you move? Especially if you have now set the ceiling for the street and are unlikely at present to recoup your investment costs in the necessary but boring stuff like roofs and rewiring?
Personally if you like the house and the area, you'd happily live there for the next 10 years with or without DC, then I'd not only invest in a decent kitchen, I'd consider extending it and doing it properly so you have the full enjoyment of it.
I wouldn't buy a pink kitchen though. Sorry. No-one else is going to look at it and think Yay! They are going to think I will need to spend £10k+ on a new kitchen straight out of the gates.
I've also had a funky vinyl floor. It was super practical, comfy underfoot and easy to clean. You had to be careful with knives though. https://www.colourflooring.co.uk/collections/vinyl-flooring