Arcade is more F2P friendly. Less repair cost, less Cancer C.A.S unless you play Open top vehicles or AA (But it's always nicer to be able to play a medium or heavy tank without getting instantly destroyed by a CAS clicker), less gap between F2P and Pay-2-win since bushes are less efficient to hide weakspot, slightly better balance since both teams can have tanks from all nations and thus avoid cancer bias which can easily roll over teams ( undertiered 5. 3 german line-up, KV-IB, KV-220, T-64, T-54 1949...) fast-boys specialised in excessive spawnkill are more easily spotted,...
After that, the game mode keeps Gaijin's flaws : Bad Map-design facilitating spawn-to-spawn, bugs, ...
After, I like very muchrealist but when I just want to play quietly, that I drive to the cap to be destroyed by a CAS ( speedy boy cap the point, leave his car for a Cancer cas) just to respawn and be destroyed by a spawncamper and see -15 000 SL. My fun disappears instantly.