Hey xplosve!
I haven't really used P5 at all, other than to poke at the demo for an hour or so. But the questions you're asking are the same sort of questions that
everyone asks when they're starting out, no matter what environment they're using: "how do I get better samples?" and "how do I make it sound better?"
Try doing a search in this forum on 'samples', you'll find dozens of threads that list literally hundreds of sites where you can download free samples from. This is a big part of the learning process, I think...when you hunt for samples, you start to discriminate and learn how to listen for the sounds you're looking for.
Have you played around with the synth units in P5? Once you learn the fundamentals of the various types of synthesis, you can start to make your own sounds from scratch.
Project5 also supports VSTi & DXi plugins, which means you can basically add to it as many virtual instruments and effects as you want. If you haven't already, check out
K-v-R, they review pretty much every free & commercial audio plug-in available. Here are some great
free ones to get you started:
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Crystal: great for pads, can create complex, textured sounds
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SuperWave PPG: awesome analog sound
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Frohmage: not an instrument but an effect unit, perfect for filter sweeps
The thing is, even though I myself prefer Reason to P5, that's mostly because by the time I tried P5 I'd already been using Reason for 6-7 months. If you're already comfortable with P5, you're probably better off sticking with it at this point, otherwise you're just going to have to go through the same painful initial learning process with Reason.
P5 has had a lot of very positive reviews, with most reviewers praising its workflow. One thing P5 does that I wish Reason offered was the ability to set up your own controls for various devices, so that one pot would alter multiple parameters etc. With this, you can more easily setup P5 as a performance instrument for example.
So that's my advice! Hunt down new sounds, dive into the synths and start looking at VSTs. Four months really isn't long at all when getting to know a new instrument, esp. one that's as potentially complex as P5. Don't worry that your software is inadequate and just have some fun