My biggest regret is not walking into a B&M way sooner. I live in what a lot of folks call 'the sticks', so the only mods I saw in person before ordering stuff was a mvp and a 134 in a tobacco store. Knowing how a mod feels 'in hand' means a lot to the quality of my vaping experience. From the weight, size, shape, button throw, position, etc. Finding a mod that fits for you would be much easier in a B&M where you can hold a few and find a style that fits.
As for the plastic tanks, ego's, etc that aren't seeing much use anymore, I don't regret them. Learning experience and great toys to have around when friends want to know if vaping is for them.