i have already used
[ROM] CyanogenMod 11.0 | Android 4.4.2 KitKat [KANG] [May-6]+[NIGHTLIES]
[ROM][STABLE][Android 4.4.4] CyanogenMod 11 with 3.0.16 kernel [July 25, 2014]
[UnORom][3.4Kernel] CM-11 Android 4.4.4 [Stable v2.0][29 July][Final]
after installing all these rom(s) and Accuweather, BBC, Chrome Facebook, Instagram, Google+, Quick office, Swarm, viber, whatsapp, twitter, swiftkey, & wordweb i get around 350 to 250 mb space left and after few days cellphone slows down a lot. So please suggest lightest & STABLE Android 4.4.4 for sensation.