Kamuela is one of our favorite parts of the Big Island. We've spent several months here over the last six years, and specifically on Iokua Place. It's a great location, close to town, nestled away and quiet. The house is great for sleeping and as a jumping off point, but is really not the best set up for hanging out. It works well for two people but you may struggle if you bring more because there is only a loveseat and a rather uncomfortable broken chair. So there really isn't anywhere to relax unless the weather is warm and you can hang on the lanai (which is gorgeous, albeit can get wet and chilly).
We also had a pretty rough cockroach infestation when we were there. The host was kind enough to send an exterminator to spray and was really apologetic, but we didn't get relief from the cockroaches over the three weeks we were there. Not sure how controllable that is but we've never dealt with this issue at any of our stays on the Big Island and made the entire stay a bit unpleasant.