Ion engines? Absolutely not. The thrust generated by an ion engine is so ridiculously low, it would be impossible to get something off the ground. Even the ion engine in KSP is overpowered, since a burn doesn't last upwards of a year...
However, in the future, there is an alternative: pulse-detonation engines.
The big difference is that right now, jet engines are burning fuel, which releases gas and smoke and all that. But doing so releases all that energy over time and in an inefficient manner, burning things uncleanly.
What make a PDE so helpful though, is its use of many many (thousands per second) small explosions rather than the burning of petrol. Using a pulse detonation engine, your craft can travel significantly faster (upwards of Mach 6), use significantly less fuel, and unfortunately, make a ridiculous amount of noise.
Basically, the concept of the PDE is that you take small amounts of fuel, drop them into a cavity, and explode the fuel, generating thrust. Due to the adiabatic expansion curve of the explosion, it is much more efficient than conventional turbine-based engines today.
The catch though, is making each explosion small enough and the explosions fast enough that the vibrations caused by a discernable pulse are gone. With a cycle speed in the 1000s of hertz, the problems of having a pulse then a wait and another pulse go away quickly.
The fuels which an engine such as this would use are likely to be the same kinds of petrol used today. An experimental flight was undertaken in 2008 using octane fuels travelling at low speed. However, many aeronautic engine companies, NASA, and the government are attempting to develop these engines due primarily due to the efficiency gains and the ability for them to maintain speeds in excess of Mach 6.
Within 200 years, this should absolutely be developed, especially since prototypes already exist. Beyond the timeframe of 100 years, however, the technology would likely be obsolescent due to something as of yet unknown.