

Litecoin is fast and cheap, and it even has MWEB — an optional confidential-transaction layer. But "optional" is the operative word: unless you deliberately moved your LTC into MWEB, and kept it there, your Litecoin is as transparent as Bitcoin. Swapping LTC into Monero replaces that opt-in, patchy privacy with privacy that is on by default, for every transaction, with no extra steps. No account required.
The usual caveat holds and is worth stating plainly: the LTC you send stays visible on Litecoin's chain. Privacy is what you gain on the Monero side. Here is how to swap LTC to XMR on XMRS.
The pace is set by Litecoin confirmations first, then the quick Monero payout; most swaps finish within 20–60 minutes. A promocode lowers the exchange fee.
Only partly, and only if you did it deliberately and consistently. MWEB is opt-in and unevenly supported, and moving between transparent and MWEB funds can leak information. Monero avoids all of that by being private by default.
No. The LTC you send remains public on Litecoin. Privacy applies to the Monero you receive.
Yes — a new subaddress per swap costs nothing and prevents clustering.