FTG actually would be better , he could mark the whole area usin amaterasu , sussano arrows , chidori varients , not to mention his haxed kunai wire skills.
Ameno more usefull for endin fights quick but not so usefull at killing higher tier people , for example , if sasuke had FTG vs naruto in VOTE he would surely win that fight wen naruto gets taged , sasuke could even of tagged naruto when their avatars clashed , could redirect his strongest RS back at him and many other things with no cooldown plus bijuu's and rikudo's chakra to spam it ..
Imagine how simple that final clash would be , sted of wasting chakra addin amaterasu to chidori , could be used to pull a minato vs obito on naruto..
He would probably mid/low diff naruto..
In the long run against higher level people, ftg is way better in the hands of sasuke than ameno..
Evem against kinshiki, the moment they clashed kinshiki would get marked then solo'ed neg diff, even momo fused would get easily solo'ed if marked.