Romania vs Serbia

Romania has no monthly cost data yet; Serbia's $1,156/mo monthly cost (across 2 scored cities) — not enough data to call a winner.

Romania's 3.0/5 safety score (across 1 scored city); Serbia's 2.5/5 safety score (across 2 scored cities) — not enough data to call a winner.

Romania's 2.8/5 mobility score (across 1 scored city); Serbia's 2.1/5 mobility score (across 2 scored cities) — not enough data to call a winner.

Romania's 3.5/5 culture score (across 1 scored city); Serbia's 3.7/5 culture score (across 2 scored cities) — not enough data to call a winner.

Romania's passport reaches 103 destinations visa-free to Serbia's 92 — Romania opens more doors without a visa.

Passport strength shifts over years of naturalisation, not months of planning, so it's a long-horizon footnote — not scored in the tally.

Romania is better connected: 24M passengers/yr against Serbia's 8.9M passengers/yr.

Romania is quieter than 45 of 87 countries worldwide; Serbia is quieter than 65 of 87 countries worldwide. Romania sees ~1 air passenger per resident a year; Serbia sees ~1 air passenger per resident a year — a derived figure, not itself ranked.

Romania runs -13°C to 35°C for most people; Serbia runs -11°C to 37°C for most people.

Depends on you — which range fits your tolerance is the real question here, not a score.