I am a young US citizen who has recently graduated with a non-professional bachelor's degree in architecture, planning to apply to graduate schools in London, Helsinki, Berlin, and Copenhagen this upcoming application cycle. I am interested in eventually becoming a permanent citizen either in the UK or EU (most attracted to London and Berlin), and would love to hear about the experiences other designers / architects have had moving abroad. 

I'm particularly wondering about: ease of finding a job, sponsorships or visa requirements, unexpected challenges, benefits + holidays, professional growth opportunities, pay, pathway to citizenship, finding your community / network, differences from the US, etc. Is there anything you wish you knew or had done during the immigration process? Was there a difference in your professional life before and after becoming an official citizen? 

Any perspective not specific to Europe or gaining citizenship is welcome. Thank you.