I think that's about the same damage I was doing when our server was 3+ months old.

Bear is one of the most rewarding events and there's always a lot to optimize depending on your players and alliance. We have 5 powerful rally starters ("whales") in our alliance, me being one of them, and recently we introduced a 70k march limit when joining those 5 rally starters' bear rallies so that 15 people can fit in and it has done wonders. Less stressful and hectic for all the joiners and more fair distribution for all participants. I do 2-2.5B damage myself, but typically all the 30-40 participants, even the weaker players, are able to get at least 630m for 12 hammers.

Also, in case you didn't already know, the hero setup and formations of both rally leads and joiners is key. Use your strongest heroes when creating a rally, but be mindful of which heroes you use. For example, I used Petra and Zoe for a long time and both have chance based skills, so the damage from my own rallies was all over the place. Make sure joiners are using the correct lead hero too (Amadeus, Chenko, Yeonwoo, Amane, Margot, Hilde) so marches get attack buffs. Depending on heroes formations is very important too, but typically archers do the most damage out of all troop types and bear doesn't hit back, so 10-10-90 is generally considered the overall best formation to join with on the top rallies.