In the interests of simplicity, if your site is really going to get "light to modest traffic,", you may find that the system performs adequately without using the nsv arrays for this data. I'd say that unless you're looking at more than 100 page reads per minute, you might be just fine, especially if you use the ACS query memoization facility. OK, maybe it should be more like 50 page reads per minute, but still unless you're really starved for hardware speed, this is very doable. If you find you are hardware-limited, consider buying faster hardware first -- you can buy a really fast machine for $2000 to $3000; what is your time worth? (Unless you're building infrastructure you intend to reuse later, in which case your time would be seen as an investment, rather than a direct cost.)
If you design some abstraction into your data access routines, you should be able to add caching later without having to rip out huge tracts of land. Pete.
