For Pete's sake, can you please submit your requests for enhancement to Oracle via your MOS account.
This forum is to help people with their questions/issues using Sql Developer.
there are many, many, many types of timeouts you can adjust via the JDBC properties - there's no free lunch however. If you get the driver to give up on a dead connection faster, you'll also miss queries that take longer than that to finish
We're not sure what you're suffering from, but it may be worth checking out a THICK connection - install and Oracle client (or Instant Client) and configure in Advanced Preferences for your connections to use thick.