I must say that I love embird, I wouldn't even bother purchasing the pe basic as you will not have to use it unless you have to use a card for your machine. If you can use a flash drive or hook your machine to your computer save yourself the money and just go with the embird.
Iconizer is a great feature that allows you to see your designs on your computer with out having to open the software.
I would create a folder in your document files, name it Embroidery files.
then you can create new folders and files to better organize the designs such as have a folder named animals, or baby designs, or names, or fonts or what ever.. when you download designs from here or purchased save them to those folders so you can locate them easily.
as far as converting designs, I would say that you will probably not really need to do that all that much as most designs on here and that you purchase either come in the .pes format which I think is what you would be using because you stated that you would need to purchase the pe basic software...??
If you find a design that you have to have, and it is not in a .pes format, then you would need to convert it. With embird it is very easy to convert it to the correct file type.
Cantoo's tutorials are priceless.. and there are enough answers here on the forum to get you through just about any problems you encounter..
Good luck with your new purchase and happy stitching..
oh I forgot to say, I have had the pe basic and pe design and have found that I could have saved a lot of money myself by just going with Embird..