My reasoning:
First of all, I don't ever imagine that standardization would happen. I agree that the politicians would never let it happen. This was just a "what if" topic for fun. I saw a similar topic on "Strategy Page" with regards to a heavy force (MBTs, IFVs, etc) I was just curious what people thought of a medium force.
I chose the LAV-III/Stryker for the basis of the armoured vehicle fleet because that is the way the major armies of the world seem to be going. I think the possibility of massive armoured battles like the First Gulf War or what we prepared for in the Cold War are not likely to happen again. Plus, I think the major armies like the the US, UK, Germany and France will likely keep some traditional heavy forces around, perhaps only in the reserves in some countries, but they will keep them around. The smaller nations like Canada, Belgium, The Netherlands, Australia and New Zealand (NATO allies) will never mount large scale armoured warfare. So might as well be equipped with top of the line medium forces.
Once you choose to go to medium forces, I think it is without a doubt that the LAV-III/Stryker and the Multi-Role Armoured Vehicle/Boxer (German/Dutch) are the best medium armoured vehicles. The LAV-III is much more developed right now, with more variants and in use by more armies than the Boxer so I chose it. Plus, Germany already had a lot of representation in the small arms and logistics vehicle areas, so I picked the North American-built LAV-III. By chosing the LAV-III it also brings a complete common fleet to the force, infantry combat vehicles, direct fire support vehicles, heavy mortars, 105mm self-propelled howitzers, anti-tank vehicles, air defence vehicles (although I didn't choose to use them). This makes maintenance and logistics much easier.
I chose not to use any heavy tracked vehicles, that is why no tank. If you were going to pick a tank I think it would be the Merkava IV because of its excellent armour designed for urban combat. The M1A2 (with diesel engine) and the Leopard 2A6 would be a very close second.
I chose the Panther armoured car (which I would type/name as the Panther Light Armoured Support Vehicle (LASV)) because it seems suitable and is in full production for the British Army. The Eagle IV could also be used. I didn't particularly like the German/Dutch Fennek. I thought it was a little small.
For small arms I chose the German G36 series because they are apparently an excellent weapon. I watched a documentary comparing them to the most modern versions of the SA80 and the M16/C7 and the new small arms being introduced in South African, Singapore and Australia. The G36 was rated as the best and proposed it could become a NATO standard weapon in the future. It has also been chosen by the US Army as the basis of the new XM8. Many of the other weapons could be just as good, but I had to pick one. The C6 GPMG/M240B is used by several armies and I've never heard anything bad about it. The M2 .50cal was a given. The 40mm GMG is similar to the US Mk.19 40mm AGL but is newer and cheaper. The Javelin is new and excellent. It is used by many of the world's major armies, US, Australia, New Zealand just to name a few (although the latter are not major armies), the British and Canadians are evaluating it right now and are likely to choose it. The Carl Gustav is also well used and the M3 version is new. The newest version of the Starstreak is dual purpose air defence/anti-armour like the Canadian ADATS so it beat out the Stinger and Roland. It comes in a heavy APC mounted version (8 missile and search radar), a light vehicle mount (6 missiles on a pedestal mount on a G-Wagon, Land Rover or Humvee), and it also comes in a MANPAD version, so it beat out the ADATS which comes in the heavy APC-mounted version. I chose to mount it on a Panther LASV because this provides more armoured protection than the G-Wagon, but is lighter and cheaper than mounting it on a LAV-III.
I didn't put too much time into choosing the MAN trucks. The US is replacing the HEMTT and FMTV fleets (even though the FMTV is new) with the Future Tactical Truck System as part of the Future Combat Systems so I didn't want to pick them if they were already being replaced. The British MoD has just signed with MAN to produce 5,000 tactical trucks in the 6, 12 & 18-tonne ranges. I looked into the MAN trucks and, according to their own website mind you, they have a 30 year life cycle and therefore are the most cost effective military truck. I also didn't think there was a need anymore for 2.5-tonne trucks. I was going to boost this to 5 tonne. MAN has a good 5-tonne that I found, but the British were procuring the 6-tonne so I just went with that. I read that the reason the British chose the MAN proposal over the US Oshkosh (HEMTT and MTVR) and Stewart & Stevenson (FMTV) proposals was because MAN could provide the entire 6, 12 and 18-tonne range, thus provide some commonality within the fleet. Oshkosh has nothing in the 5 or 6 tonne range and the S&S have nothing in the 180-tonne range to my knowledge. Common fleets is my whole goal. The G-Wagon was also a tough one. It could easily have been the Humvee. But the US is again replacing the Humvee with the FTTS and the G-Wagon is still new and I read that at least 7 NATO armies already use the G-Wagon. Plus, like the Humvee it comes in the "jeep-style" transport (LUVW to us Canadians) and the 5/4 tonne light truck version (LSVW). Again the LUVW, LSVW, MLVW, HLVW and VHLVW fleets have been reduced to two common fleets: G-Wagons and MANs, greatly simplifying maintenance and logistics. And both are German, which might simplify things even more.
The HIMARS was no contest. It is really the only new, truck-mounted rocket artillery system being procured. It is a smaller version of the MLRS which is widely used within NATO. It would of course have to be mounted on whatever truck the force is using.
The helicopters were a really tough choice. There were so many good choices I had to list two of each, but I could have listed more. I chose either the Tiger or the AH-1Z Viper because they are very effective armed reconnaissance/attack helicopters already in use with several armies. I stayed away from the AH-64 Apache on purpose. Although very sophisticated is very expensive to procure and to operate. Its maintenance requirements are enormous compared to the Viper and Tiger. I didn't think that it was a wise financial choice for the smaller countries. The medium helicopter could easily be the NH90, the Black Hawk, the EH-101 Merlin, the H-92 Super Hawk or even the Cougar (although I didn't like the cougar as much) What I like about these choices was they could also be used as ship-board helicopters for the navies and SAR/utility helicopters for the air forces, reducing the logistics and maintenance burden even more. The Chinook was a given. Widely used, tested and trusted. I also have a lot of trouble picking a tactical UAV. I gave up and didn't even include it.
