Great fight, I'll take Obha to fight his way to a close decision win after a rocky start from feeling Arbachakov's power. His jab and workrate will be the difference over Arbachakov's overly patient style.
Ohba’s probably the safer pick just because he mixed it with a higher level of opposition but Arbachakov could definitely win this.
This is pretty much my view too, Jel. Oba's wins over Chionoi, Gonzalez (could have gone either way, tbf), Chervet, Chartvanchai, Villacampo & Hangata are substantially superior to Arbachakov's best wins, which aside from his 2 x very credible victories over Kittikasem, amounts to not a great deal, relatively speaking, in Zamudio, Soto & Un Jin. Yuri doesn't half pass the eye test, though. Who is the greater Fly based on their respective records and quality of opposition beaten? Oba & by quite a distance. Who was the better H2H? I haven't got a clue & whilst I agree with your rationale that as the more proven fighter, Oba would be the safer pick, I couldn't pick either with any confidence.