Chris to answer your question, you need to become more creative around the greens. There will be times when the 7 iron will be unsuitable. For example a sand trap between you and the green.
I was the other way around - very s/w dependant. Coach has changed this.
Trust is a big thing in this game. Chris, when you practice correctly you will find that you will have the confidence when out on the course.
Here is a little snippet that I practice. I stole this idea from one of Dr Bob's books and I changed it to suit my lifestyle needs.
Chipping;
3 balls from 2m off the green to the pin with my 7, 9, pw, sw, lw. Then,
3 balls from 4 m off the green with the same
clubs, then 3 balls from 6m off the green with the same
clubs.
I do this 3 times per week. I do it from the same area from the chipping area to the same pin position each session.
Chipping/Pitching;
5 balls with pw, sw and lw to 10m, 12m and 14m targets. 5 balls with pw and sw to 30m, 40m and 50m marks.
I do this 2-3 times per week.
I incorporate my preshot routine with each and every shot.
I've found this has helped my confidence on the course.
I apologise for the long winded response guys.