INIT strings caused nothing but problems for me. I use BTAnytime as the IP. I didnt do any tweaks to get that ping, and I doubt any tweaks would really improve it.
Thats not to say tweaks are bad, on my winmodem tweaks did improve my connect a little. Some tweaks will harm ping, for some it can help a lot, so its worth trying. Also if you do tweak your modem, DONT use modem tweak program, as they usually badly effect gaming performance.
It all comes down to 3 things in the end, ISP, phone lines, modem. You can improve 2 of them with little problem, but bad phone lines can be hard/impossible to fix. Check your line for line noise if your ISP seems good and your modem is good, yet you still get bad pl. Phone up your phone company and tell them that your net connect sux, they may be able to do something for you. I remember when I was on a winmodem BT managed to cut about 50 out of my ping by increasing the gain on the line.
Happy Fragging