A 10er a ticket and still stick to the 650 with 100 free/44 remaining??? That would probably have people way more excited to be fair.

If you plan a cheaper ticket but doubling the allocation then there is no real benefit.
The appearance of over valuing the car is probably your biggest factor; and if you change to a 10er, while it's just a tenner people still want that the sense of value for money.

But if you mean sell the remaining at a tenner, doubling the current ticket holders, then you'll build a head of steam...get onto the 2nd one and keep momentum up by breaking even and then look to build from there!