Good. Bad. Makes no difference. They are MEGA. They shake things up and keep a player on their toes. If the player is good he or she can always turn them into his or her favor. A bad player on the other hand...How would you turn the 5pc/wk galactic speed limit (enforced by the game, not by the UP) to your advantage? The AI rarely if ever builds ships faster than ~10pc/wk with all of the engine tech bonuses applied, so the idea of it crippling your opponent as well just doesn't apply.And no, abusing the movement bug is not a valid answer.(If you want to know what I'm talking about, look under Beta Reports, but it applies to all versions.)
I used to build super fast ships but not since SD nerfed the amount of engines I can slap on by increasing the size.
Granted, I've never had the (dis)pleasure of experiencing the "ripping spacetime" speed limit mega event. And since I play Huge galaxies it would most definitely slow my game. But it would also allow me to slap more guns and defenses on. Possibly even more life support to my reach is extended at the cost of my speed.
Here are a few examples of how I spin a galactic mega event:
Pirates - Time to focus on infrastructure. Your ships are going to get smashed and so are your opponents. But run up a branch of the offensive weapons and create a pirate killing ship. Time your building of them so you get a fleet at once. Clean out a small sector of space (pirates tend to camp out in a certain area). Repeat until you have some room to work. Build super fast transports. Invade defenseless enemy worlds.
Jagged Knife - Love this! Build transports, en masse. Take your planets back and then some. Get free techs. And you never have to go to war with any major races.
Peacekeepers - See Pirates above. Do I have Tech Victory on?
Sure, when these things happen I roll my eyes and mutter "aye carumba!" But I always try and turn these into my advantage.