If you frequently deal with LED projects and have to keep the cost down then macroblock MBI5030 Starter Kit would be best fit for you. Chips from other major manufacturers like TI and so on.. are nice too, but for a similar set of features they make you pay a lot, especially for small quantieties. It may be worth to have a look at the MBI chips, maybe even build a small stash of them. That saves shipping costs in the long run.
This is a small development board that will get you started with the Macroblock MBI5030. Macroblock is a Taiwanese manufacturer whose product line includes a wide variety of very affordable and quite capable LED driver chips. They’re available at kingelectronics, a US based distributor for them.
The MBI5030 is a 16-channel constant current LED driver with 16/12-bit PWM. You send your data just once, feed the chip with a constant high frequency ‘grayscale clock’ and it takes care of the rest. Many AVR chips can be programmed (FUSE setting) to output their system-clock on a certain pin. That option is quite suitable to drive the ‘grayscale clock’.
You can download design files and relevant information from GitHub: https://github.com/madworm/MBI5030_starter-board