Like anything else, the centerboard is a compromise, you gain some things and lose some things. If the cable breaks it is going to be in the down position. If you can't find an anchorage that is more than 11'm deep you will have to go for a swim and rig a line to pull it up some from on deck. I think it is a good idea to change the cable before you think you need to - it is not very expensive and not too hard to do.
For what we are doing I think it is certainly worth the complication. being able to go to weather really well could be a lifesaver in some conditions. Being able to get the self-steering working better by balancing the helm is going to save the crew's energy so again a safety thing. If we hit something I assume it would be pretty much straight - on and the board would push up. Never experienced it because we always have it up when entering an anchorage (the default position is up - we just lower it when we need it for a particular reason).
One comment about 'big windows' I had a look at the Discovery 55 at the Annapolis Show a few years ago (helping a friend who was actually in the market for a boat that was close to $1.5 miilion. It has very large windows in a deck saloon arrangement so I asked the sales manager about them. He said that they are laminated, tempered glass, permanently bonded to the cabin and stronger than the fiberglass - they certainly looked impressive. I doubt that similar windows on a cheaper boat would be built as well, but you never know. Maybe I don't have to sit down with the designer, the Discovery was an incredible boat - but I don't need a 55' even if I could afford it and the draft was pretty deep as I remember.
If I was going to look for a boat would I say it had to have a centerboard - no, not at all, but I think on balance it is a useful feature. If I was sitting down with a designer to have my perfect boat designed would I require one? Probably not, but would discuss the pros and cons with the designer. Heck, Ted Hood is still designing in his mid 80s, might see what he would have to say about it today.
Back in the water in Grenada - with new main and #2 and cockpit canvas (Santa came early). Will spend the winter and early spring in the Caribbean and then head to Bermuda and the northeast US. Still trying to decide if we will bring the boat to Canada, either in 2015 or 2016.