As a realist loyal NYC-based passenger who values many aspects of B6, my reaction is simply this: Most of those ideas sound fine, and they won't really impact loyalty. I think surveys will probably yield results which say nobody wants to pay more for anything. But if the B6 people read this board, they should know that some of us just like your airline, and will accept many of the changes needed in a tough economic environment, so long as they aren't disruptive to the basis good customer service and convenience we should expect, whether we pay more or not.
1. Yeah, charge a nominal fee for upfront extra legroom rows. Get the revenue from that. My only suggestion in this regard is to continue the practice that all of those unsold seats immediately become available at the 24-hour check-in window, and stop charging the fee at that point. While I won't pay for this service, there are too many hypersensitive passengers out there who will. It won't impact the experience that much.
2. I am somewhat resigned to the fact that B6 expects a revenue stream from the internet. In all honestly, thats OK. I think it would be a mistake to charge for the TV/radio, however. It really is something that makes me more likely to pick B6 over a similarly priced DL flight, particularly transcons.
3. Charging for priority boarding: Go ahead. It also won't impact a whole lot here. However, the only issue here is that those allowed to get the priority really need to be monitored for the carry-on requirement. I think this is only fair, as no amount of money should get you around the rules everybody is supposed to follow.
4. Curbside check-in: I have to laugh at this idea, only because , at least at JFK, one of my biggest complaints is how frustrating I find the curbside area. I typically check-in from home and then use the AirTrain to get to JFK. The curbside area is reserved for those who did check in at home, but the line is usually filled will clueless people who then clog up the sidewalk, making the curbside check-in both slower and more frustrating than just going inside and using the kiosk/bag check lanes. So the irony here is that I think they should go ahead and just charge for the use of curbside, because, as a loyal customer, I wouldn't miss it anyway. It was so poorly done for so long, its lost its intrinsic value already.
5. Priority bag drop off: There can be a charge for this, but I really really really wish there would be a dedicate priority line/agent(s) for those who 100% checked in at home. So maybe this can be that perk that is missing? What would be NICE would be to have a priority line where they charge a fee for people in a rush, OR, waive the fee for those who present the printed boarding pass at home. My feeling is it would improve the crowds at check-in at JFK, thereby saving staffing costs.
6. Some ideas not being floated around but things I thought about (some of which I might pay for):
a. Charge an extra dollar for wine/beer if you actually would like a real glass rather than a plastic cup. I loved the wine choices. (Tried them last month when I just really needed a drink

but would have liked a real glass.
b. I am currently not a B6 cardholder, but I suspect I would think about it more if there were some intrinsic benefits, including an override of the fare requirement to get up front, or use the priority line. Not sure I would pay for this, but some might.