It seems to me that one of the most obvious kit-bashes for the Maiden would be a longer ship. I'm not sure how the net end result would turn out, but for those interested, here's a parts list for two different approaches (done with 1" squares in mind...the instructions are easy enough to translate into other scales):


3-mast Long Maiden:
(Requires more care and customization)

Step 1:
- Print 1 additional Middle Hull. Include it in the Hull build at either end of the existing Middle Hull.
- Print 1 additional "Middle Deck #1" and "Middle Deck #2". You'll need to add 8" to the Deck length, so cut the first 5 squares from MiddleDeck #1 and the 3rd - 5th (from the bucket on down to the next-to last row) from MiddleDeck #2.
- Assemble the middle deck in the following order...partial MD#1, full MD#1, full MD#2, and partial MD#2.
- Use additional bits left over from the MiddleDeck scraps to cover up the white spaces on the two lower hull pieces marking the "old" mast support locations.
Step 2:
- Print 1 additional Left Middle and Right Middle hull piece. Include them end-to-end with the original Left Middle and Right Middle hull pieces.
- Print still one further Left Middle and Right Middle piece. You'll need to cut "patches" out of this to cover up ratline gluing points you won't be using.
- Do not put the middle ratline ledge into place (only the rear one). Cover up the four white patches with bits cut from the extra Left Middle and Right Middle pieces.
- Print an extra page of Hull Supports, spacing them evenly throughout the extended middle hull.
- CAREFULLY line up your upper deck central mast hole and place your central Mast Support accordingly.
- Add the two missing central Ratline Ledges, centering them on the just-placed central Mast Support.
Props:
- Print out 8 additional cannons and, if you are so-inclined, an extra page of transparency windows to cover the extra lower-deck hatch.

4-mast Long Maiden:
(Requires more work (added pieces) and time)

Step 1:
- Print 1 additional Middle Hull. Include it in the Hull build at either end of the existing Middle Hull.
- Print 1 additional "Middle Deck #1" and "Middle Deck #2". You'll need to add 8" to the Deck length, including another mast support, so cut away the top half of Middle Deck #2 (the first 3 full squares, down to the row including the bucket) and the bottom half of Middle Deck #1 (including the full row above the big hatch, leaving out the first two rows only).
- Assemble the middle deck in the following order...full MD#1, Partial MD#2, Partial MD#1, full MD#2.
Step 2:
- Print 1 additional Left Middle and Right Middle hull piece. Include them end-to-end with the original Left Middle and Right Middle hull pieces.
- Print an extra page of Ratline Ledges, and put the ledges on the marked locations of both Left Middle and Right Middle pieces.
- Print an extra page of Hull Supports, spacing them evenly throughout the extended middle hull.
- Print an extra page of Mast Supports, mounting the extra mast support on the marked space in the extra middle hull piece.
Step 5:
- Print 1 additional Mast, including the extra Lower and Upper Yard, and one additional set of Upper and Lower Ratlines from the transparency pages. Assemble and insert as with the other "center" mast.
Props:
- Print out 8 additional cannons and, if you are so-inclined, an extra page of transparency windows to cover the extra lower-deck hatch and an extra rope galley for the extra mast.

Note: There is one distinct flaw in this approach, in that it will result in not having the cannon "draglines" match up properly with the locations of the cannons. Getting the Upper Deck to to this properly would be difficult in the extreme.

Disclaimer: Thus far, these are only theories, and have not yet been actually tested. Attempt at your own risk, ideally after completing a "standard" Maiden first.