Well guys, it seems that Caspio has been listening to our concerns regarding the cost of data transfer. By pure chance I've just revisited the pricing section of the website and discovered that their pricing plans and content have been updated. It appears that Caspio is sensibly giving much more help to the smaller guys, while loading the higher fees on to the larger companies.
Data transfer is now "unmetered" from the professional plan upwards. I'm assuming that "unmetered" means 'free', although I'm not sure why they don't just say "free". I hope it's just semantics and that I'm being over-suspicious!
And a quick glance shows that pivot tables are at last included in the professional plan. On the downside the professional plan still doesn't include pdf downloads (why not??!!), and the number of datapages is restricted to 50.
But overall the changes to data transfer bring a huge sigh of relief to business start-ups like me. It also means I can be less paranoid about measuring specific cost efficiencies of my datapages and use that time on buidling my business instead.