As above, you'll really need to get rid of all the off-site links etc if you want to list on eBay long-term.

That aside, more searchble keywords might help, by which I mean things relevant to use of the item, which you have in the description (where you mention briefly that it's designed for parties, boating, fishing etc) but not any of the titles. Perhaps you can also explain a little more about how that will be useful in certain circumstances, even if most people would understand (eg I can see them being popular at parties, a bit like a more expensive wine charm if everyone had a different colour - so, portable party lights and stubby coolers in one! 😄 , or any other situation where someone might be drinking in the dark and need to easily locate it, I suppose).

You also mention that you offer custom coolers - I didn't spot a listing where buyers can have them customised, but I think you might get a bit more interest if you can set up a listing or two at pre-set prices, and (if needed) you could limit the options for customising so cost won't exceed what you've allowed for in the listing price, and you might pick up a few more gift-buyers, especially at this time of year.