opinions on my plan for adjusting calories for maintenance--ADVICE!!

Okay, so i'm 4'11 and maintaining my weight...well trying to. I do cardio for about 30-45 minutes per day 6 days per week, 2 days it is pretty intense for 45 minutes, the other 4 are moderate for about 30 minutes. maybe 4 days a week i strength train for only 10 minutes each time. i do pilates for about 15-25 minutes 2 days per week. and of course the casual walking around campus to and from classes. so, i estimate my burn to be about 300-400 not counting the walking. 

i've been eating 2000 calories on the not intense cardio days, so 5 days per week and 2100 on the other 2. so here's my plan. 

if i've gained i think i'll do 2000 2 days a week, and 1900 on the other 5. this will bring my total to around 700 less per week, which is about 1/5 of a pound...so as long as the scale hasn't jumped up like a pound, i am in a good range. if it's more than 1/2 pound i think i will scale it back to about 1800 5 days a week, and 2000 2 days a week. Which would put me at 1200 less than i've been eating, so about 1/3 of a pound. i don't want to assume that whatever i've gained is "actual weight" so i'm not trying to match it perfectly. If the scale reads .75 greater than last week, i'll assume at least half of it is not "real weight" since it is highly unlikely that i've over eaten by that much...it would require an extra 375 calories per day and i doubt that 1600-1700 is my range with my activity level being taken into account. So, i will count it as half that, which is overeating by roughly 150 per day, which would put me at 1850 5 days a week and 1950 2 days per week. since i want to keep the numbers whole, i would do the 1800 and 2000. does this sound like a good plan?