there is a spare parts application in JJ RSL7 go there and switch off windows animation, fancy input animation, transition animation etc, that might help to reduce the lag.
Edit: battery life has definitely improved with JJ RSL7, android system is almost consuming nill battery now, wonder how is this happening but battery usage is definitely better, the UI is pretty responsive too, I installed the angry birds holiday season and it was so smooth, on stock rom, it always use to hang! bw did you guys install these plugin -
Japanese_Jellyfish_RLS8_ahb_overclocked.zip (50% AHB bus overclocking at speeds above 600MHz addon)
Japanese_Jellyfish_RLS8_hw_ui.zip (Addon to enable hardware accellerated UI)