It seems to me they put the random number generation in the wrong place. They do the roll as you enter a res instead of during the spawn. In theory, it should be a trivial fix, in theory.
That way you'd end up with more smaller ships than larger ones, but you'd get a fair spread of them over time instead of the current situation where it tends to lock to a specific set of ships.
That way you'd end up with more smaller ships than larger ones, but you'd get a fair spread of them over time instead of the current situation where it tends to lock to a specific set of ships.