After looking at the range of available equipment from a power perspective, there appeared to be two groups, one in the 600 watt range and the other at or near the 1.5 kw legal limit range.  Knowing that the latter would give me only slightly more than a 3db difference and considering the cost difference, the choice was easy...... to set a power cap of 600 watts.

The 600 watts power limit also gave me some mechanical advantages.    I was able to use lighter weight coax, RG/58, which has a power rating of 700 watts up to 40 meters, with acceptable loss.  Outside my shack I have a tall pine tree (center) supporting separate 160, 80 and 40 meter dipoles arranged in a star configuration.   The hanging RG/58 is thin enough to be almost invisible and the (sag) weight is much less than larger coax.  Another weight consideration is use of 50 light weight ferrite beads for my feed point chokes.   A forth advantage is less bulk as it enters my shack.  

I use RG/8 (from Davis RF)  for 20 meters and up.  

Both beams are rated at 600Watt, ideal for my Elecraft KPA-500 watt amplifier and KAT-500 autotuner.

Pine tree center support.  3 dipoles.
= Tree
12 / 18
vertical on metal car port roof

2 meter J-Pole
directly over shack
(not showwn).
@ 35ft

160 meter
w/ loading coil in short leg

40 meter

80 meter

56ft (aluminum ladder)
tower w/ 5el 6meter yagi
All band 500 ft Loop @ 30ft high supported by trees.  Feed line is 450 ohm window line and drops to balun at roof edge, then 10ft RG-8 into shack.