Hello and welcome to planetside 2
glad to see new players joining.
ill try to answer some of your questions.
1: I dont know the exact pattern of where you can redeploy or not, it seems as if it lets you redeploy to a nearby large facility, a nearby medium and a nearby small. I dont know for sure though. (I think the reason for that is to force players to use vehicles i guess instead of just warping about on the map...)
I usually spawn a Valkyrie and fly to where I want to go because the Valkyrie works like the Galaxy does, you can jump out of it from the air without taking falldamage.
2: Yes cert grinding is slow, and it used to be even slower...
There are many videos on youtube explaining how to earn certs, so do look into that. (just make sure you watch a video thats not too outdated)
The biggest cert drain is vehicles and construction, so watch out for that lol.
Personally i earn the most certs when using vehicles. About 130 certs per hour as a Liberator gunner is my record i think.
3: I have thouoght about that too, but i dont know about any plans of merging them.
(personally i like the times where its a bit calmer :P)
4: Im pretty sure there isnt a way to see the current server pop, atleast in the game. Maybe theres a 3rd party website that can provide that info.