ipad Pro 12.9 2nd Gen poor battery life

So I have an ipad pro 12.9" 2nd gen. It's the 512GB with cellular + wifi. At max brightness I'm only getting 4-5 hours of usage. I've got it paired with the apple pencil and that seems to be running rogue. Before I had it paired I could get maybe 6 hours. But when I'm using the pencil for sketching or painting I dip down to just about 4 hours of usage. Max brightness seems to take a lot more of the ipad Pro than it does on other devices. Even my 4k Razer Blade Stealth with an older skylake CPU seems to get better battery life on max brightness with a 4K display. I'm only using about 55GB right now, and I still haven't added my ipad to my data pool so that might be eating up a little battery. Apple quotes 10 hours, and I know that's with lower brightness but I'm lucky to get half of that. Is this abnormal behavior? Or does the ipad Pro really guzzle power at max brightness?