since playing defensively is your style, this is an example you could use. the oponent is a 1550-1600 n00b so it's just a demostration(he quit soon after I started my titan gate)
I didn't play a higher rated player because this is the first time I've tried this and might not work for ppl above 1650+ (let alone 1700 if I used my real account :p) but with some modifications, you can use it to defensively turtle and build titan/wonder.