Trying to make a Sampler

I am trying to make a sampler with the following functionality:
Cross Fade looping
Ogg Loader

What’s the easiest logical route to achieve this in JUCE?

Why don’t you have a look at the SynthesizerVoice and SamplerVoice classes in the documentation?
Those basically lay the groundwork for what you want to do, but of course there are several blanks to fill in.