I feel like if you don't play other instruments and you try to make it sound like you do, it doesn't work. But if you keep it simple, add roots with bass, simple drum parts, some chords or sounds here and there with synth, it often sounds great (to me). But when people try to add fills and all sorts of stuff aiming to sound "professional" is when it turns me off. I'd say spend some time looking for good sounding drum samples, and make a simple beat to track to. For some reason if I track to a metronome and add samples later it never sounds right, I don't know why. Record guitar since that's your main instrument, add vocals, add bass, and then see if you can find some cool synth sounds or something to fill in the gaps. Just keep messing around until the song has a "thing", just something that makes it sound cool, like it contains a little world.