For the most part, these are very sucky. A refit is supposed to be an improvement. These don't end up being an improvement because of the exorbitant cost involved, combined with the random nature of the refit. While I can see the randomness being apropos as you can't always guarantee the available resources nor, in the case of the crew refits, the effect combat experience will have. However, since your refit has already been earned by trial by fire, so to speak, why then does it cost you more points? You've paid already. Yes, the ship would be a bigger prize to the enemy and this could be reflected by increased VPs, but since you've had to earn the refit and it's random it shouldn't cost any more points.
Also, since ships are not, for the most part, new, but instead have usually been through several campaigns then it stands to reason that refits should be a part and parcel of ordinary fleets. So, for one-off games I think that refits should be available. Though here they can cost points. Either individual costs based upon actual value, allowing the refits to be selected, OR an averaged cost and some level of randomness, be it totally random or allowing the player to choose the chart and then a random roll or whatever.
The two concepts can even be combined. Such that at the start of a campaign you could have some ships with refits, costing extra points, but then earn some more "free" refits as the campaign progresses.