Thanks a lot everyone! This was very helpful!
I think I'm going for Sirui r-2204 + Va-5 based on Marc's suggestion. I could get them for under 400 € which would also leave something in the bank for future upgrades. ;)
I'm almost set on getting Kowa tsn501 + 20-40x zoom as my first scope but I have no clue how good (and pricy) tripod and head I will need for this lightweight scope.
I've spent last two days reading about tripods and heads since I have zero experience of scopes. I've learned a lot from this...