You will always fly past your aim point. Your aim point is only for the purposes of the approach, then you level out and flare, and you will always fly past it - how far depends on your speed. In a short field landing you will be slower, and won't fly as far past, but you will still fly past (unless you have a very abrupt arrival!) If you need to touch down exactly at a particular spot, you will adjust the aim point to a point before the actual touchdown spot.
It does sound like you are a little too fast. If you are too fast the aircraft will be more sensitive to your back pressure, and more likely to climb again, which both mean it is easy to end up too high in the flare. The J170 manual online at the Jabiru site recommends 65KIAS for the approach speed, so that is the speed I would be aiming for (check your aircraft POH), preferably stable on speed by 200 feet. Trying to slow from 70 to 65 "over the fence" will also make you high - speed and height are both energy, so you will just trade one for the other.
As for looking down the runway, the best advice I have heard is when the runway looks like a highway, look down the runway like you are driving a car. It's probably more like 3-400 metres ahead rather than the very end of the runway, but the important think is not looking right in front of the aircraft. It sounds like you have the idea there anyway.
I would not recommend using the flight simulator for this, the last 20 feet is probably the time when the flight simulator is least helpful in showing what you need to look at and feel. There is no substitute for practice in the aircraft.