Hi Charles! Welcome to the addicting and exciting world of home audio.
I guess I should start with the basics:
Ableton Live is a program that is rapidly becoming one of the more popular software options for recording, producing, and playing back music on a computer. It is
split roughly in half between the classic 'timeline view' for audio software and a grid of cells, with each cell able to contain anything from a single drum hit to an entire song.
These can be 'mapped'(have each cell assigned to a button) to controllers, so you can press a button and have one of these music files play back instantly and completely in-sync with the rest of the music. One of the cooler features of Ableton is that it has powerful beat-matching features, so you don't have to worry so much about when you start the file or whether it's properly beat-matched to the rest of your audio. It also allows you to record audio just as you would in Audition, and then apply realtime effects or processing to the recorded audio.
There are many options that you can choose for a drum software. Probably the most popular is Maschine by Native Instruments. This actually comes with a pad controller, which they promote as being able to control 99% of the software without having to touch a mouse or keyboard. The standard version is around $600 and the bigger 'Studio' version is around $1200 if I remember correctly.
This controller and software is easily the fastest I have ever used to create beats for my music. It comes with many gigabytes of sound content which you can splice together, sample, effect, and sequence into your own beats. It also has many premade 'kits' so you can pick a good starting place to quickly tap out your own beats.
I have not yet worked with WaveDNA, but it seems incredibly complex for simply creating a beat. We provided them some of our controllers for them to test with their software, and I don't think they were able to make them work together.
The M-Audio
Oxygen line is a very well-established inexpensive line of keyboards which plug in via USB and send MIDI to software on a computer(no actual keyboard audio output without a PC). I actually use the M-Audio Radium49 at home(one model up from the Oxygens) and after >10 years it's still working fine. It's very plasticy and not the most durable thing, but if it's just going to sit in a studio and not go on the road that should be ok.
You mention you're somewhat averse to the 'dippy' generic MIDI sounds: Fortunately, with software, this isn't an issue. Most instruments are very rich sounding, and don't sound like a 1980s Casio preset unless you want them to. To this end, Maschine also has excellent sampled synthesizer sounds that are included with it, and can be played with either the pad controller or another keyboard.
Aside from well-known synthesizer software like Maschine or Massive, you can find a *huge* array of free and paid instrument plugins that will work within Ableton or most other DAW(Digital Audio Workstation) programs. There's a wonderful directory provided by a site called
KVR Audio which allows you to search by price, operating system, workstation software, and type of synthesizer or effect. I also personally love my Arturia V-Collection synths, which are some extremely high-quality classic synthesizers in simulated software form.
I know that's a wall of text, but it's a good start! I hope it helps, and shout if you have any specific questions.
-Rob