Yep, exactly. The nodes or your LN address is the destination. The channels are different paths to get to that destination. If one of blocked off or closed you can take a detour and still arrive to the destination.

Also thinking about channel fees similar to a toll for passing through that route: Having multiple channels allows your node to find the best (cheapest) path to the destination.

Nah, no need to have multiple nodes. That's what custodians are for. Have your node as your primary payment method, but keep a small amount with a couple custodians in case your node is down, so you aren't completely out of commission until you can get your node back up.

Am I understanding that you set up your Alby Hub with a 50k sat channel? If so, you would have been better off sticking with custodial lightning until you have enough to establish a few sizeable lightning channels (1m+ sats each).

You also don't need to have 3m sats to set up three 1m sat channels. You just need to have 1m sats and some additional sats to cover a few on-chain fees. What you do is open the first channel for say 1.1 million sats, then send all of that back to yourself on-chain using boltz.exchange. Open the next channel for 1.05m sats with a different channel partner, then send that back to yourself on-chain too. Finally, open the last channel with another partner for 1m sats. You can then send most of that back to your cold-storage if you don't want to hold much of a balance in lightning, and you will end up with more than 3m sats of inbound liquidity while only costing you the amount of 5 or 6 on-chain and lightning fees and two Boltz swap fees. Do this when on-chain fees are low, obviously.