Reasonable acquisition to expand the Volvo Concierge [0] services. The digital services are likely the strongest selling point in a few years when luxuary car makers all offers self driving, electric powered cars.
If the differences between css3 and no-css3 is so small as in this test (a few rounded corners, some drop shadows and some tiny gradients), you should totally go with pure css3 since it'll get easier to maintain but still look decent in old browsers. If you're having heavy artwork which will have huge impact on the experience; go with images (perhaps a mix?)
Agreed. Heroku makes it dead simple to use their Varnish proxy. Just set one http header and they'll cache the page for you. After that, your app doesn't do anything until the cache expires. This obviously won't work for highly dynamic pages, but for semi-static front pages/blog entries it can be a lifesaver.
[0] https://www.youtube.com/watch?v=YPKDy7k5hHE