1.Is it logical to travel to the core with a little gunship /freighter/yacht ?
Well... Domina did tell you to go the core, and "If life gives you lemons..."
2.You have maximum 7 slot for device, but there are lots of necessary device .
This is mostly true.
I suppose this is to force the player into deciding which device are absolutely necessary rather than just installing every device you can find.
There are workarounds like modded ships or device slot enhancers (which still do not override specific limitations like the freighter only being allowed 2 weapons)
5.Should not there be some life support goods (like you must have some water ,food etc),that makes the game more realistic.
This has been discussed but George had a great reason for not doing this. Basically, it would not add to the gameplay at all, be a minor money sink, and a big annoyance. Fuel is used as the sole 'upkeep' resource and I think it should stay.
6.I think carrier should provide player a spacial frigate or destroyer after gaining the rank of Captain or beginning ships should change as the game has been updated.
The overlays have given us the ability to change the LOOK of the playership midgame although none of the stats change. You should check out Bobby's
Holographic Stealth Device