However, he is fairly popular among players along with mitsu and pat i think. Cerv you should learn to get familiar with the match up along with mitsu, pat, and pyrrha.
I will research those characters for you. Xiba isnt a zoning character and his spacing is only good because of his movement. He only has range because the opponent can space him to keep him away. He is built the idea of temperance.
Ex: against natsu 3B and 3(B) are very good. If natsu wants to get selfish with damage by punishing 3B with A:6 then xiba can counter with 3(B)..... and get much more damage than natsu's punish
Ex: (i will test this again to make sure) 6B ~ K will evade her A:6, BB, AA. (Again they are getting selfish with damage.) If they use reactions for 2As .it will ve hard to tell between 6B ~ K and 6B B+K for most players on reaction
A friend has actually told me there is a way to access rememberance faster based on his channeling kick inputs. Being the fact he likes to screw with my head...i really dont know, but if i find something i will notify you.
4A is an excellent move against raph and i guess ivy. I you block something and cant punish it at range than just close in if you want to make an offense.
For your problem with natsu, just block her. You will need to know what options are the safest when blocking. Spacing is strict on that part too. Try to bait her into using 22A. Then use B+K to counter it. I will research them for you.
Xiba 1A isnt good. There are set ups for it, but 6A beats most in terms of damage. 4B is good against people who like to JG at mid range, mainly if they are looking for xiba's 6A.