Thanks for all the useful comments. Done all I could up/down hill; some work just requires the machine to run cross-hill. I could sometimes get around this by mounting the BH bucket backwards - anyone ever try this?
Like EastTexFrank, I find that my tolerance for tippiness varies widely with time of day, tiredness, how long I've been working in that area.
I've also found that reflexes (so far) seem to work in the right direction. When lurches, awkward loads, a stone or soft spot have made the machine very light on one side, hands and feet automatically move things the right way to bring it all back in balance. Main thing is to HOLD STILL and think before doing anything sudden. Nearest tipovers have actually come from a sticky valve on the BH, which I'll ask the dealer to re-repair when I can spare the machine for a few weeks.
Like Awert, I have no idea how strong that roll bar is. Can it really hold up two tons of moving iron? Not that I want to find out!
Attached pic is where I'm working now.
-NBB