The tow mission is often overlooked. In fact using the tow mission
properly is often the key to winning the game. The reason for this is that
engines are very expensive. They cost huge amounts of minerals and MC. By
using the tow mission you can cut this cost considerably. Instead of
building Merlins, LDSF's and STF's with tech 10 engines you build them with
tech 1 engines. You can simply just tow them arround. This will save you
almost 3000 MC for every Merlin. One strategy example for the colonies
could look like this:

Turn 1: Build a Cobol with tech 10 engines
Turn 2: Build a LDSF with tech 1 engines
Turn 3: Build a Cobol with tech 10 engines
Turn 4: Build a LDSF with tech 1 engines
Turn 5: Build a Cobol with tech 10 einges
Turn 6: Build a LDSF with tech 1 engines

At this stage you will have a transport capacity of 4350 KT. This will
allow you to colonize planets much faster than your enemies. The large
transport capacity is especialy important when you find planets with
natives because you only have to visit them once with a large frieghter
whereas your enemies will have to shuttle back and forth several times with
smaller ships with hightech engines. Your ships wont have to return to pick
up clans as often as smaller ships. Which ships to build and how many
depends on how rich the game is. The above example is intended for low or
medium games. If the game is rich it would probably be better to build
SDF's instead of LDSF's. The game might even be so rich that saving cash
and minerals is not important and you might decide to build all ships with
tech 10 engines to allow for higher flexibility. In my opinion games this
rich arent real games because all economic considerations are rendered
unimportant and after all VGA Planets is also a game of economy.