What kinda wattage should one be pushing for good skip? and would a preamp help?
T23
Preamps merely make your noise floor higher, but can OCCASIONALLY help.
Height is might. Get that antenna 30+ ft in the air.
Antenna design. You'll do better with a yagi than a simple dipole.
Feedline. Don't skimp! RG8U / Belden 9913 / LMR400 for runs greater than 50 ft.
Lastly, wattage. This is by far the least important.