As a songwriter, you are able to express YOURSELF. I find that I'm happier with songs I write that represent me when I'm honest with my audience. There are times where you can sacrifice an idea or a line for an easier rhyme that doesnt sound like something you would say; however, would urge you not to do this. Find a way to express yourself honestly and take the time to find the right words that fit.
Being lyrically honest doesn't automatically make your song approachable to the listener, but it sure does make it easier. Your listeners are very intuitive and will be able to decipher whether you're being authentic or not in your writing. It takes time, but you'll develop a personality in your lyrics that is uniquely you. If you can pair your well-crafted, authentic lyric with a killer melody, watch out! Because that is dangerous combination for a hit song.
What's the most honest thing you have ever written? Have you ever thought about making that into a song?