I don't think there's a much easier way to do it but some DAWs definitely make it easier than others.

I totally get what you mean, I tend to procrastinate doing it because bouncing things to me just seems like a lot of work and like I'm using hard drive space holding samples that I'll likely never use (let's forget about the thousands of downloaded samples I have actually never used...).

However it's really not that bad. I just have a "Project Specific" subfolder in my "Samples" folder that holds a million tiny little samples that I need. Most named "_____ Reverb", haha.

It's a combination of pitch and time stretching the audio 

Wouldn't time stretching also pitch it down?

I've used dBlue's TapeStop before and I like the effect. I'm aware of kiloHearts' new TapeStop plugin as well. I've tried in the past using spectrum analyzers to see if I could figure out what exactly the effect is, but I'm not that great at that sort of stuff.

It's not just being pitched down, obviously, so what else is in the effect?

EQ: Fabfilter Pro-Q (Can't go wrong)
Reverb: I'm between on this right now. I was using Lexicon but it was causing problems so right now I'm using FL's stock Reverb 2.
Delay: Typically integrated synth delays in Massive or Harmor for example.
Sidechain: Fruity Limiter or if I want a constant rhythm then Kickstart.
Compression: Maximus
Saturation: Maximus?
DAW: FL Studio

Nexus has got a bunch of nice pianos. They're nothing ridiculous or groundbreaking but they're not too CPU intensive and they're pretty damn good.

Are you using an audio interface? What audio drivers are you using? ASIO drivers are recommended. Also play with your buffer size setting. Turning it up will be safer quality-wise but will increase latency as well which isn't good for playing synths and stuff.

Definitely a quick, sharp attack, and almost always layered with a flute/woodwind instrument. I haven't found a way to synthesize the entire lead in one plugin, you basically need to layer.

If I'm attacking an idea by attempting to compose and arrange the entire thing first I'll just use some simple VSTs like a Nexus piano or even FL Keys and just something like BooBass for the basslines.

Normally I end up starting sound design earlier than I intended but sometimes I try to get the entire composition and arrangement done first. I'd avoid using straight midi just because it's really no effort to throw a vst in front of it and make it sound a little bit better.