1. Maximum parameter size per transaction
number of bytes per transaction for a single transaction is limited
several constants, in particular an upper size of for operations
max_operation_data_length and the hard gas limits for operations
and blocks (a block contains a set of operations):
An implicit account will be deleted as soon as it's emptied. However, if it's a registered delegate, it won't be deleted. Also, if the implicit account is delegated, you will not be able to empty it, unless the delegation is withdrawn first.
You will not need to repeat the reveal, only the burn to reactivate by the sender.
When you transfer out of an address which has never revealed its public key, you must pay a burn to do this reveal operation. This was added back in, IIRC, 004 to prevent new address creation spamming.
If you transfer the entire balance out of a tz1/2/3, then you must again pay the burn fee to "reactivate" the account. The blockchain does a type of ...
In Tezos, gas does not have a monetary translation. It does not "cost" you anything to execute a contract with 10 gas vs 1M gas. Gas is simply an internal limitation to prevent contracts from running amok.
After asking, there is no equivalent of a gas price in Tezos. You pay a transaction fee, and this fee should include everything. Doing some stats on the fees you may get an upper-bound on the gas price.