Words of wisdom from the old guy! Practiced medicine for 30 years, before I quit to make kayaks (retired.. lol). I have kinda been following this thread, so I though I would put in my 2 cents.

Metatarsalgia is generally related to bad foot mechanics, may be congenital, but not likely unless you are a youngster. Years of use and abuse and poor footwear (the sins of our youth, we all did it) and carrying to much weight can cause laxity in ligaments of the feet, and resultant maldistribution of weight, and resultant inflammation and pain. The recommendation of custom orthotics (from a Podiatrist) is the right one, along with weight loss, and your NSAID (aleve, Advil, aspirin, etc) of choice taken regularly in therapeutic doses will help this to improve. It can take up to 2-4 weeks for many anti-inflammatory meds to do there anti-inflammatory thing, so ya gotta take em regularly. Nice cold foot baths in the evening, especially after being on your feet can help also. This is a weight distribution problem, made worse by impact, so insoles, which don't alter foot mechanics probably wont help much in the long run, but may give some temporary relief if they are well cushioned.

Along with the above I would avoid sandals, flip-flops, or even walking barefoot until your pain begins to improve, get yourself some good running shoes that support your foot and ankle to lounge around in.

As much as I can think of right now... I am old ya know, but at least not Ancient!

Ric A.