You have various options.
If you want to use it only in one place, use the dataview webpart as Vladi suggests. If you want to reuse it, you can still create new XSLT web parts and copy the XLST code.
If you want to make it comfortable for the customer to add a webpart here and there on his own, you should develop your own web part.
If you want your view to be available over the default page of the list, you need a custom view. The advantage of this is that you can use your view whereever you display the list (using a ListViewWebPart). On the other hand it probably takes the most effort to implement it.