It is mainly because those items are guaranteed to help you familiarize yourself with the ins and outs of using them. They are a big help in making you feel comfortable when you push off with your feet while also balancing on top of the board when riding. It is not good to go for a very technical product, so it’s best to choose the mentioned types first.
To get higher ollies, I would suggesting resting your back foot on the very end of the tail and the front foot in the middle of the deck to allow for more slide. Popping as hard as you can and catching your board in the groove of the nose with you ankle practically resting in the groove will level the board out in the air. after this initial movement slide you feet back to the bolts on the tail and nose to ensure a clean landing.