Hi there, the Free 1250 has a LOT of power and lift, would be fairly close to the HA 1500 yes. The 1000 Free is my most used foil and that of most of my "crew" here in Bavaria, a really good allrounder, with good top speed- you can get that up to 44-46km/h fairly easily. At your weight I would either go for the Free 1000 or the 905 Glide, the 1085 is a great foil, but I do not think it will give you the speed/it may have a touch too much lift for you if top end speed is what you are looking for. 1085 will have plenty of Glide, but so will the 905, which will also be faster....
For more speed, try moving your foil backwards and with 70kg, you could easily go to a 75L board for sure, I am 76kg using 75L and 65L all the time, after learning and using 120/95/85L boards before. That will help a lot too.