Advice for solo trip (24F) to Central/Eastern Europe and Georgia

Hello everyone, I am planning an approximately 1-2 month trip for mid-May 2026 that would include Georgia and other countries in Central and Eastern Europe. I am specifically interested in Soviet/communist history, brutalist/modernist/all-around unique architecture, and a mix of gritty, weird, and charming cities. I plan on starting my trip in Georgia, and I will likely spend around 10 days to two weeks there. After that, I will either head to Estonia and travel southbound, or to Serbia or Bulgaria and travel northbound from there (whichever is most efficient).

the cities that I have in mind right now Are Belgrade, Sofia, Plovdiv, Brasov, Sibiu, Budapest, Prague, Krakow, Wroclaw, Warsaw, Gdansk, Lodz, Vilnius, Riga, and Tallinn.

Other cities I’m curious to explore: Sarajevo, Mostar, Ljubljana, Skopje, Kaunas, Narva, Brno.

Specific sights I would like to see include the Buzludzha monument and Hill of Crosses

Obviously I will not be able to see all of these cities, so I’m looking for advice on which ones are worth seeing. I’ve backpacked western Europe for 1.5 months before, and I think my biggest mistake was trying to see too much in too little time.

I plan on budgeting approximately $3000 and bringing a credit card too.

Any advice for my itinerary?