Don't try to write it a certain way, you have a piano now, just play it and sing it how you naturally sing it, record it (nothing fancy, room mikes/tape deck etc) and listen to the play back. As you listen think about the beat, tap it out with your hands... if you have any drum programs (casio?) play around with different ones until you find something that feels good... think about other parts.... at this point you should be getting an idea of what kind of song you have. I use GarageBand for this... developing ideas... but I always start strumming acoustic, tapping out beats with my feat... singing away (badly ) but then use this to develop the song... I rarely think about what genre it might be until I start picking the drums out.
It appears to me you are trying to pigeon-hole yourself to guide your songwriting, "I write POP" etc.. I say just write for now... concentrate more on writing good songs than writing "INDIE" songs or "POP" songs. Instead try writing in something other than 4/4 (or MODES ) but allow your writing to develop, don't force it a certain way... not yet.
Sorry I didn't want to appear I was lecturing you or anything... it's just when I read your post I get the vibe that you are someone who likes to speak through their music, no wimpy love songs here, good strong lyrics (can't comment on your playing ) but you are unsure of the direction you should be taking.... IMHO I say for now don't worry about writng a Dixie Chicks stlye country song... write a Lindsey style country song.
I hope somewhere in my pot induced ramblings there's a nugget or two of wisdom... nite all, Geo