Keeping wallet addresses outside bitcoin core

[Bitcoin]

Keeping wallet addresses outside bitcoin core

I'm trying to build a good security for my online bitcoin based application. Is something like this possible?

send_bitcoin(address)
create_address()
sweep_balances()
       +
       |
       |
       v         New transactions
+-------------+  <----------------   +--------------+
|             |                      |              |
| Wallet keys +--------------------->+ Bitcoin core |
|             |                      |              |
+-------------+   Submit signed tx   +--------------+

The "Wallet keys" will be my hot wallet. There will be another wallet store which would be used for cold storage. The "bitcoin core" will be some trusted public node that I don't control.

Does using this architecture have any disadvantages over running a full bitcoin core to keep addresses?

I need to get callbacks for new transactions on the list of addresses in my store, that is not managed by bitcoin core. Is it possible using this method?

My reason is that running a full "bitcoin core" takes up too much computing resources & disk which is expensive on cloud and by doing this I can avoid having to run and maintain a bitcoin node. I can submit a signed transaction to any trusted node.

Thanks.

Source: Keeping wallet addresses outside bitcoin core