Since you said you have a collection of hardware, i would suggest Sonar or Cubase (or Logic if you have a mac). All are 'traditional' sequencers, that is the left to right looking interface with different channels for audio or midi. Sonar 5 (producer edition) and Cubase SX 3 are both excellent pieces of software, and you can use hardware or vst synths in them. Same applies for Logic, except you have to use the mac format of software synth, although Logic comes with basically anything you'd need, and basically most plugins come in AU format for mac too.

You can just call up a midi channel, and patch it to your hardware, and edit the midi note, CC, nRPN data etc all on the screen. Works exactly the same if you load up a vst, just with no external synth or midi cable. Just make sure you have a good soundcard with midi output and a good audio quality for recording the hardware sounds.

The other option is to go with Reason. People coming from an old-skool hardware setup are perfectly suited to Reason's style. All the virutal hardware boxes patch together with virual cables at the back, and apart from being able to record audio, or use your hardware synths, Reason can do basically everything you'd need.

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TranceTribe Recordings

you should first try some demos and then consider what other ppl say.

id say FLoops cause its so easy to do what you have in mind instandly. it has a step sequenser so you can program your drums without using stupid drum machines or w/e. the best piano roll ive ever used. its pattern based so when ideas strike you just jump to another pattern and go crazy withour fucking up the rest of the song.

its not limited its just not like cubase..ppl that bash it do it just to look cool anyway lol. get the demo.

reason would be a pain in the ass for you. there are no audio tracks like in other sequensers, no midi output/audio in so forget your h/w and there are only 2 synths so its kinda limited. its a good addition to any sequenser tho.

id say fuck cubase but then again thats just me(never liked anything in it).

ive used sonar a couple of times and it seems to me to be the best and easyer in the daw category (cubase logic etc).

logic has a tough learning curve but i like it, ive heard good things about it and it seems really powerful. (tho i havent used it much. learning curve you know lol).

thats what i think/know about software studios... hope this helps