Its a fact that the intended way to get the best gear/blueprints is via open play. This is how the game is set up, how it was set up in Division 1. However, there is clearly a % pool of blueprints that rotate through the vendors. Drawback is that the vendors change only once per week and there's only a few of them.
Blueprints - If you want blueprints the best way currently is either running Missions that gurantee a blueprint OR clearing Control Points of level 3 or higher. This is the intended way it seems to filter Blueprints into the world, by achievements rather than just purchasing for the vendors.
Again though, Ubisoft/Massive have made it clear they've done all they reasonably can to not divide the player base. This means ALL items are available by ALL means but with significantly varying degrees of drop rates.
Example: An exotic has the opportunity to drop from an enemy, a control point cache, DZ landmark box etc. How HIGH the chance it drops from these is different, with a higher chance of it dropping from the activity the developer felt when they made the game was the higher risk task.
Remember, when we work with game development we are working with drop rate percentages of 0.004% very often. I'm serious here and I don't believe many people realise, in order for the systems to work a game virtually never works with a full percentage value as that works out far too high based on the number of times an action is undertaken by a player. So mostly for rarer drops a percentage hit is around the 0.004% rate.
These are drop rate calculations I've seen in many games I've worked with, proviso here is I haven't been privvy to the actual drop rates for Divison 1 or 2 as yet but I work on the same assumption as they're calculations that work with other MMORPG's.
This is why a guaranteed drop is always a nice touch. So rewards of missions on higher levels, or clearing control points is currently the best option by far. WHAT blueprint you do get however is, again, based on a drop rate % (see above).
Another way the game is more inclusive is with exotics you build. BTW - you can collect parts in any order, however, blueprints only drop AFTER you have all the parts and the levelling up blueprint only becomes available once you've built the exotic at its 450-490GS. However, these are open to all players...solo or groups and I feel the materials have a scaling drop rate. You're first drop will be fast, then it scales the % back as it goes along.
What is clear that as you get further into the game "useful" items drop less and less unless you engage in the higher risk activities (higher level missions, PvP activities, DZ, ODZ and eventually Raids). This is completely intentional as its intended as a form of brakes to slow you're progress down so you DON'T hit end game before the game is expanded.
