It probably thrives in an rpm range of 600-1600 rpms, based on that freakish bore/stroke ratio.
I believe that as long as it can breath well, it’ll rev high. Nonetheless, the power probably sinks like a stone as the revs build.
Diesel explodes when compressed, it doesn’t need a spark. I would say that glow plugs aren’t needed, because the whole system is probable kept and an optimum temp at all times to facilitate the burning of Diesel.
Nangleator
When you get to large diesels, which are usually static such as in generators or shipping, you don’t have oil changes in the way you probably mean.
Engines like this have large lub-oil tanks which is circulated by large pumps, the leakage is often so great that the lub oil simply collects in a giant catchment baseplate and is then pumped into waste oil tanks.
The waste oil is then loaded into road tankers to be recycled.
There are some large engines that have support machinery that can perform some oil cleaning, such as centrifuge oil/water separation or forced pressure plate filtration, where high pressure oil is forced through plates with minute holes which can trap contamination down to a certain size.
On diesels you don’t have spark plugs, you simply inject very high pressure fuel into the cylinder and the injector units themselves are designed to atomise the fuel.
As you will know, when you compress a gas, it becomes hotter the more you squash it.If you have a fuel/air mixture then there will come a point where the mixture becomes so hot it will self-ignite, thus there is no need fo a spark plug in a diesel engine.
Large diesels will almost certainly have turbochargers on them.
The exhaust gases contain a lot of energy and some of this is used to drive the turbine impeller, which of course is then used to compress the incoming air to the engine.
As stated before, compress a gas and it gets hot, and this reduces the density of the air, so there is generally a unit in the incoming airflow that will chill that air.
The result is cooler and more dense air, which makes for more fuel/air mixture into the cylinder= more power.
The turbo is what really makes diesel engines on this scale economic.
Other bolt-ons
The exhaust gases having driven the turbo still contain lots of energy, and these can be diverted into a chamber inside which is a bank of tubes with water fowing in them(this is known as a waste heat boiler).Through the tubes water is pumped, and the resultant hot water is then put to use in heating, or (perhaps suprisingly to non-engineering types) into chiller units that are capable of running large air conditioning units.
The diesel itself has to be kept within certain temperature limits, so it has a water jacket, just like a car.The water gets very hot, especially if it is a pressurised sytem, and heat energy can be recoveverd from this by putting it through a heat exchanger which is used to heat up water in another system - such as heatin.
The lub oil also gets hot, and again heat energy can be recovered by pumping it through an heat exchanger.
Although this particular engine is being used to move ships around, it would not be unusual to have a generator driven by it also to provide the power to operater the ship.
Please humour me as I have very little mechanical knowledge, but are 2 stroke engines more or less efficent than 4 stroke engines?
2 stroke engines are less efficient-
Of course it’s real - I have the 12-cylinder version fitted in my mini.
Probably looks something like this! 
I recall seeing an antique steam engine somewhere in England, which has been pumping water since 1840 or so…it had an enormouse bore (around 5 feet), and the rocking arm was something like 25’ long! Engineers attribute its longebvity to the extremely slow piston speed…the thing will probably run for 500 years more!
That’ll be this one.
http://www.kbsm.org/engines/90.stm
However this will not remain the largest beam actuated steam engine in the world for long as it’s companion is being restored.