wow, that seems like it should definitely be enough to handle your gear.
if you're going to buy a new one anyway, maybe just buy a second 1000VA(or 850VA even) for JUST your receiver.
when I bought my f8500, that was the first time I ever 'maxed out' my 1000VA UPS. it only happened when I had the tv, xbox, and receiver going. I guess those were the highest draws.
are you powering down devices when not in use? that could be a cheap solution as well. if you have something like a harmony remote controlling things, have the receiver power up first, maybe that will avoid the spike that's setting off the alarm. and of course, keep everything not being used turned off.
I had, at one time, my HTPC(with 8 external drives), 360, ps3, wii, dvd changer(200disc), cable box, pioneer 1018 receiver, and plasma tv(50" then 64") all hooked up through a 1000VA UPS. I ran into issues with the larger tv, but moving things to the surge only side fixed all my issues. IIRC, everything related to the computer, game consoles, and tv were on the battery side. the dvd, cable box, and some misc chargers were on the surge only.