This is a good improvement to Nping's packet crafting capability, but I'm not sure I agree with a few things:

• having a hardcoded default that is not documented
• Having separate options for "default" vs "raw"

I would like to see this split into a few different changes that each offer an incremental improvement. Then we can evaluate each separately and merge them faster:

1. A --tcp-options option that works just like your --tcp-options-raw in this PR. This matches the naming scheme used by --ip-options.
2. Enhance the --tcp-options to take a symbolic representation like --ip-options does. We have something like this in Nmap's OS detection where we use single non-hexdigit alpha letters to indicate the option, then append a hex value to each. So your default options would be encoded as "M5B4NNSNW7". You'd have to add a new syntax for timestamp, maybe separating the TSval from the TSecr by a colon (":").
3. Add the --ts-increment option. If the --tcp-options specified by the user does not contain the TS option, it would be appended to the end of the options and padded with noops as necessary.