You Strengthen the Network
You can Vote on a fork/change
Privacy when you transact through your own node
Help Decentralise
Check the Hash rate
Check Transactions/fees on the Mempool
Open Lighting Channels to provide liquidity for the Lightning network,
Run a BTCPay server
Coinjoin your Coins
Even View Ordinals if that's your thing.
Plus more....

The reward is that you don't have to trust anybody, as you can verify.

Good karma. You're doing something to help humanity and that karma will be repaid