You can't delete the pre-come apps like stocks, but you can put them on page 2 (or 3 or 4), way on the right, so you never see them (except by mistake when scrolling to the right too fast).
I don't know what you mean by docks. You can have 16 icons per page and up to 9 pages. That's 144 icons, plus the four on the bottom. That makes 148 by my estimates.