A few thoughts on that Alex.
The first is, don't set up that redirect! In short it won't help you, for reasons such as potential duplicate content, confusing to visitors, and you'll have to choose where to link to...
If you own the original .com, then this is where your main efforts should lie. Directories, happy customers, and industry blogs will be more inclined to link to your companys site if it feels more legit.
Depending on the keyword difficulty, focus on making some linkbait content, be it a free online calculator or tool, or a free PDF download, or just some standard infographis and try distributing all of this content to relevant niche sites and social media.
In answers to your questions then;
1. Hyphens in this case will not have a negative effect on your URL. I believe Google will start clamping down on hyphenated keyword rich domains, as shown by the recent google branding serps update, but the timescale and effectiveness of this is unknown.
2. Don't go the extra mile and 301 the domain, unless you're keen on building links to both sites it's simply not worth it, focus on your main domain and optimise the landing pages for your keywords.
Solar Monster