A conventional drop out really works best for IGH if you are looking for economy and ease of use, and as stated allows for easier wheel removal if you run fenders which are almost mandatory on most commuter bicycles.

An eccentric bb and vertical dropout is nice solution but does add cost as a decent eccentric will add costs and they are not totally problem free and more complex than a conventional bottom bracket.

There is a little learning curve when it comes to removing and re-installing an IGH wheel on a conventional frame as you have to know how to set the chain tension and dial in the shifter, the vertical drop out and ebb eliminates this.

Track ends are a good solution when you are not running fenders and tug nuts can be used to easier alignment of the wheel and tensioning of the chain.