1. Mobile-friendly PoW (CryptoNight Lite). The current PoW is not ideal for smaller devices because the 2MB scratchpad is too large for the cache size on most mobile and lower-end desktop/laptop CPUs. A tweak to use a 1 MB scratchpad would allow it to run efficiently on lower end CPUs including some mobile processors as well as much better performance on mainstream desktops/laptops. Credit for this idea goes to the Louisd'or project (crypto_zoidberg and doe1138), although they didn't clearly explain the benefits of it.
Feels strange to me. Why sacrifice original CryptoNight?
We are going to very strong ARMs now, with lots of fast cache, look at MediaTek, look at Apple A7/A8, look at AMD servers with arms, pretty good performance for an original CryptoNight. I got your idea, but i think in that case "light" cryptonight will be less secure.