... Also in the newer versions you can bump the fee for a transaction
after it has already been sent
Only if the transaction is marked "replaceable"... which, I think by default, only occurs with what Electrum defines as "low fee" transactions... otherwise you have to go into the "tools -> "preferences" -> "fees" and select "Always" from the dropdown for "Propose Replace-By-Fee"...
Also, only the Sender can try and bump the fee... if you're receiving bitcoins and they're unconfirmed due to low fee, your only option is "Child Pays For Parent"...