I have just released a package entitled "MoleculeViewer", whose functionality is exactly what it says on the tin.
This package was inspired in part by previous efforts by @BoB LeSuer and @Bianca Eifert. I took the best parts of their packages, along with some of the good parts of the built-in molecule renderer, and added a few of my own tweaks. One noticeable tweak would be the depiction of multiple bonds (just like what is done in some physical models), as in the following image:
MoleculeViewer["thiacloprid"]

The package has a number of other nifty features and auxiliary functions, like highlighting:
MoleculeViewer["caffeine", Highlighted -> {"O", "N" -> Orange}]

and legends:
MoleculeViewer[RunOpenBabel[GetChemSpider["calicheamicin", "InChI"]], PlotLegends -> True]

Before using the package, you will need to install Open Babel for some of its conversion functionality. Additionally, to use the ChemSpider search functionality, you will need to register to obtain an API key.
Download the paclet from GitHub and install in the usual manner. Alternatively, using the technique featured here, evaluate
PacletInstall["MoleculeViewer", "Site" -> "http://raw.githubusercontent.com/tpfto/MoleculeViewer/master"]
Documentation and a gallery are given as separate notebooks.