Laterite is much better added to a tank while it is being set up than after it is already running. It's extremely easy to end up with a cloudy tank if too much of the laterite is exposed to the water. Much easier to use just root tabs.
How much light are you planning to put over the tank? If you stick to a low to medium light tank, then
CO2 and heavy fert dosing shouldn't be necessary. Some occational Traces and Potassium would be the main things that you would need to dose. As long as your Nitrates and Phosphates don't start to bottom out you wouldn't need to dose them.
Flourish Excel is a liquid carbon supplement that can be used instead of or with
CO2 injection. It does work well, but
CO2 works better. It's an ideal product for smaller tanks where
CO2 injection may not be practical.