Water Heaters - Looking for a Water heater

Currently i have an oil tankless boiler that is responsible for heating the house via steam radiators and supplying all the hot water. While it is only my wife and I now, we do plan on starting a family so our hot water demand will obviously increase. I am trying to figure out what kind of water heater we should get. Like i said, the boiler is supported by oil, but we also have a gas line for our stove that i could tap into. Does anyone have any thoughts on which tank i shoud go with, oil or gas? Also which size tank i should be looking at, as well as trusted brands? And finally, is there anything else i am missing on what features i should look into? Any info would be helpful.

Thanks,
Pat

If you like tankless and have had good success with them, then go for a high end tankless for your needs. If not, go with a gas tank heater sized to accommodate your future needs of your family.