Go next step,
15" 
Though i wouldn't overestimate strength of those wheels. Forged doesn't automatically mean superstrength. Often they are as strong as cast wheels, but chosen to use up their advantage of manufacturing/material to turn for lighter weight. Given from your threads on that ohlins suspension and stated use on backroads/rallying, imho it's not that hard to break/bend these. The more hardcore rallying one go, the more imho worth to consider real rally wheels .. downside being very heavy weight. Well, but they can get you till finish with flat tire
Though CE28 of course at very least will be of reasonable strength/rigidity. I wouldn't be so sure for their further lightened, SL versions, though.