I give up...
I wish you had set your post out as a list of things so it would be easier for me to reply to each point. Lol oh well I’ll try and cover all your concerns here….
1 – Try and open the page up and open the “watching” page (has an eye icon). If there are any there selected click the icon to REMOVE it from the list and it should remove from the corner of your screen. Do this to remove all and you should have a clear screen.
2 – Get a bigger screen, set the UI to the biggest you can (in settings) just before opening the TP or better yet leave it at that size.
3 – I main an engi myself and this is one of the reasons I don’t use turrets. Besides that turrets just suck all around in most cases especially since you want to always be on the move anyways. Unless you are farming a very small area why even bother with turrets?
4 – The game is designed in this way on purpose with regards to shooting/attacking enemies who can’t reach you. It’s to stop exploiting such as bots etc being able to kill things without risk. Only way you can play “smart” like this is in WVW and really only on other players or mobs under attack from your allies.
TP – no idea, people just don’t pay atention I guess or are too lazy to go to a vendor to sell their stuff…
Hope that answers some of your probs lol…