Consequences to reducing `checkblocks` in console on a node?
checkblocks and checklevel are simply for local sanity. It's just making sure when your node is coming up that things aren't completely crazy, it won't catch malicious alteration or set any flags anywhere. If the checks fail the node won't start up at all and will show nasty error messages. Turning them down in all probability won't have any impact on you, the only downside is that if your node state is left inconsistent the sanity check might not catch it.