After fully researched, Phidi seems to be the only race that is at a disadvantage with respect to make new planets and terraform to the best suitable planet for their race.

The process got choked at just after creating new planets (Barren), the terraforming option is to Glacier planets, unless they can come about to 'acquire' other races that allow them to sit in the planets they want to terraform to Arid, after which Coral terraforming option is opened regardless of any race is on that planet.

Just my thoughts, after going through all the different races. I'm just curious if this is an intended path for the Phidi race. Cheers!

The terraforming system is going to completely change in the next DLC.

Right now, terraforming in an endgame system that usually comes into play long after the game is already decided... so I'm not sure that it has very much to do with "balance."

Q: Is there a [Right-Click] to inverse select ships before going to battle?

I understand what you're saying. This question is more from a point of view of 'pure' race or play style where one (me) goes around and [bombard all]+[build colony] taking only a few secs after conquering the planets, than to carefully bombard planet until they can be captured[invade] with 100% chance... too much work in comparison... so to 'keep' foreign races. obviously this/my simpler play style is not very suitable for Phidi, IMO.

As to the 'end/late' game point where the need to terraform more planets can be different with different game settings.
I'm currently doing the
- Brutal
- Large(88stars) map with Phidi (again),
- rare minor races with
- frequent raiders in a
- Sparsed out star map
- against the maximum no. of AI.

In this Sparse star map, expansion is extremely difficult for everyone except a lucky few, and I'm now moderate(2nd largest) controlling the smaller half of my side while Orthins is having 10s of Dread Stars vs my 1 Dread Stars+many other ships from the races I've Allied-Annexed. Story short for my strategy is to snipe at their planets while keeping them at bay from my own, until I have enough Dread Stars to do damage to the much much more superior fleet... so maximizing economy/planets is very important for me now even after all research is already done but most of my planets are only at Arid.

As a Phidi race, I can't do the most suitable terraform for Phidi without a 2nd intermediary race like the sand...something. Thus my question about Phidi race can't do their own terraforming on their own unlike the other races.. IMO if someone new were to try Phidi 1st, he/he is gonna have a really good shock. Haha

It's exceptionally unlikely that a new player would start a game on Brutal with the settings you mentioned.

However, as I said, the terraforming mechanics are going to be completely changed.