I can tell you my personal experience about this. I play in eu region, merged server 291-306. My server is more or less 8 months old. When my server went in the cross server realm was around march and at that time i was level 73 breeze dancer too and i was anbu rank, so more or less i was in your same situation. I tried for a while to rank up in arena and for the whole 1st season (that lasted just two weeks) i got only defeats. My total initiative at that time was something like 5500 with 1700 on prompt move 1. So i ended up the season at 19-4. I retried arena at the end of march. My initiative in the meanwhile went to 7000 with 2300 in move1 and i got mei, mabui and tenten gnw so i went water. I managed to reach jonin rank but then i suffered only defeats again an so i ceased to care about arena, overall because my friends used to tell me wasn't possible to win in kage or superkage. So for 4 months i played like if ranked arena didn't exist with my rank as jonin 26 -5 frozen there. I've began to do ranked arena again just last week. Now i have 12500 initiative, 4250 in prompt move1 and i managed to reach halfway to superkage rank pretty easily with a han, roshi, sailor sakura team that is a team that with some efforts you can easily have even by being full free to play simply by hoarding in 5-6 months ~300 seal scrolls and 3200 coupons (since you'll be able in the meanwhile to do the other 60-70 draws you need by using free draws).

In the very early times you'll face indeed a ton of problems also in training since your server is right now the newest one so the one with the lowest average initiative but the more you grow and the more you'll find casual players, from other servers weaker than you + newer servers than yours will be added to the circuit and so all will become easier. This week in particular is a special one since there are both the annoying missions from mission general mobilization and the shinobi feast event so for people like you is not exactly the best moment to join cross server arena, but you'll see since next week things will be easier because people will start again to join arena training mostly for the daily missions or to test teams that don't work at all as they hoped they did and those are the battles you can win. Moreover you'll find people like me that after they beat a person if that person joins again simply chooses to refresh the browser to give him the free win or people that join just with main to let other kill him.

Don't deject, things will be better later, but just beware that for a long while arena for you and all your server will be a pretty hard match.