In my experience I've never spent a single euro/dollar on anything in this game and I'm pretty sure I managed to capp 53k before I hit lvl 80 in Germany which was the highest power for that level in the entire merge excluding only one high spending player that had around 58-60k at 80. As of right now I'm lvl 87 and 66k with my main team and 67k as my max bp. If you want to find out whether your BP is above average for your level you just gotta compare it to the rest of the players in your range of power and level. Also you gotta be proactive in how you manage your resources and prioritize power over character pool if you want to grow.

A few tips:

1. Use that broken plunder system, it gives you 150 cps for 3 successful plunders and what does the convoy give you? a few thousand coins and only 35 cps that are not even guaranteed.

2. Save up on cave keys, seal scrolls, refinement runes, charms and wait for rebate events.

3. Quit doing useless plot instances and focus on gaining power, this way you'll dominate sage world and therefore you'll get more rewards, don't worry it's not cheating it's just you being a smart player and abusing the system.

Can't think of anything else right now so if there's captain lurking around here I demand your knowledge NOW!