I've not really used any older Line6 modeling, just the Helix, so I'm not familiar with the typical Line6 software editors. The Helix family has it's own editing software that is free to download called HX Edit (for PC and Mac). It works with the Helix Floor, Helix Rack, Helix LT, HX Stomp and the HX Effects. It works very well and is easy to use, but the Helix has to be connected - you cannot edit patches with it "offline". I've used Amplitube and Guitar Rig is a similar fashion that you are intending to do with BIAS - and they worked great, but having everything in one floor unit, like the Helix does, and not having it tethered to a laptop is just so much easier.
Bad news is the Helix will blow your $1000 budget, but a Helix LT is quite a bit less expensive and has exactly the same engine, effects, amp models and processing power as the full Helix. It's just missing the scribble strips and has fewer effect loops, inputs and outputs. TBH, I would buy the Helix LT now, since I don't really use any of the upgrades on the full Helix Floor.