You are a NW3 V (barely). Even though you have no history of balding, hairloss has attacked many here with no history of HL. Meds will usually halt the progression. It could progress over 15 years or over 1 year (it can be quick sometimes). It is a difficult thing to predict. I started losing my hair at 21 y/o and look like I have a full head of hair and w/o avodart, I would look awful (That you can take to the hairbank!). I started propecia at 25 and avodart in nov. 2002 and haven't look back.
First thing is to HALT your hairloss, then evaluate.
BTW, I had no sides on propecia, and with avodart, I'm still fine.
Like I said, you need to stabilize your HL then talk about number of grafts. Once you do, maybe 2,800 - 3000 for hairline and crown, but I can't stress enough about halting the crown. You should start (after meds at least 9 months to 12) with the hairline with around 2000-2500 and see if propecia regrows the crown, as I feel it will!!!
Still wait until 9 months and see if Propecia help with the front before doing a HT.