Here are some usefull tools I received from more experienced players when I started playing this game (some years ago)
Beginner guide: http://www.kongregate.com/forums/12-kongregate-multiplayer-games/topics/755389-heart-of-galaxy-hitchhikers-guide-to-the-heart-of-galaxy
Some tools (battle calculator, research calculator, info...): https://godlloyd.github.io/HeartOfGalaxy/
I dont know all, my personal record is getting to the third galaxy (got only few planets there), but I will try to answer some of the questions if you need
Most people choose Ishtar Gate as the HUB planet in the first galaxy because it is sort of a crossroad (center of map). For HUB planet to work well you need to have 1 Auto-route for each planet to deliver 105% of everything to the HUB. You might have to allow "Advanced options for autoroutes" option. I recommend you to allow all the options in lower section of options menu - It will allow you to make planet send resources for construction to any other planet (considering you had sent some ships to HUB fleet). If you do it correctly, everything will be managed automatically from the hub planet.
Personally Ishtar is the best HUB for me in the first galaxy because I use web browser script that allows me to create all auto-routes with one click - or when the auto route fleet capacity is not sufficient I can top up all autoroutes at once with a single click.
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