Well it basically bools down to:-
1. Different soldiers wear pants at different heights .
2.Different soldiers have different width of legs
3.Different soldiers have different length of legs, some have huge legs and some have not so huge legs
4.Some prefer to have relatively tight fitting around knee pads, some prefer loose fitting
5.Some prefer to mount knee pads at higher side of knee while some prefer lower or middle.
Solution:-
1. Custom pants for all operators (not possible)
2. Have integrated knee pad height adjusters along side width adjuster for knees.
Now for height adjuster you will have to have extra cloth for length tucked inward which will make operator uncomfortable , so you either use thin soft stretchable material or have second inner layer between which the the tabs will lie,
Crye usually tuck height adjusting tabs in pockets with extra cloth around it
Width adjuster near knee is not that difficult to produce ,whats difficult is to make sure that strap do not make operator fee uncomfortable.
You have to also make sure that your knee pad support structure is big enough for it not fall out and thin enough for operators comfort, thats just about knee pad.
Lets not talk about materials and straps for pockets and placement of pockets and other shit.
I understand your points but for the regular issue soldier it can be simplified to certain extent .
1. Size of pants can make a difference in the placement of padding . For each size the length can vary upto a certain optimal range . The increase of size of pockets would directly be proportional to that of pants .
2. For the issue of different heights of soldiers wearing uniform , one can use different stuffing for their Knee pockets . But if I'm not wrong there is a specific length of knee pockets which might stay unaltered since the size of regular pad stays the same irrespective of user . This also means that despite the difference in sizes , the snug fit can be ensured .
3. Now we can't adjust and customize everything according to each different user or soldier since that hampers logistical unity . The thing can be an avg military grade , which doesn't mean the highest quality but it means that a functional and efficient instrument at a reasonable cost . Ofcourse the quality wont be as high as that of 3rd party vendors or Crye design but it would be functional enough for regular infantry and would also be easy to produce en masse .
Also if you notice this , you'll see that the regular US arny pants didnt come with velcro width adjustor in their knees , ankles nor did they have knee pad sections . But currently since you can acquire Multicam from almost any open sources from any part of the world , they used private acquisitions when their apparel or tactical eqts needed replacement . Now you have thousands of sources , in america itself e.g. Rothco ,Crye , Patagonia (replacing crye in some special forces units ) as substitute goods .
But this facility of ours has been put on a hold , since Indopat has been solely proprieted by NIFT and Army . The share of IPR has not been updated , and the supplier yet to be identified . The first 50K delivered to some frontline units (I myself saw it) , international exercise teams and high brass officers . Unless one good supplier gets selected , we wont see the necessary changes to the design .
And acc to my assumptions , instead of selecting a tactically experienced firm , they're gonna go with a regular firm with high amount production capacities