Overall I don't like the idea of a race selection preventing a global event. Using the pirates as an example It's sort of screws with the whole risk Vs reward of Crystite that I don't think should be tampered with.
Valid Point.
The idea was that since a lot of discussion focused on sentinels or buying insurances against disasters, having the Packer eat up all crystals not sold to hide them from pirates might have had some appeal

Of course it influences rather heavy the outcome of that event.
Land auction on race selection
Current land auction it's possible to not gain a land, but I'm assuming you need/want everyone to pick an avatar for the round. How will this be handled?
The auction is used to decide the order to choose races, so the pick of the races would be right after the order has been auctioned.
Instead of re purposing the land auction, I've always pictured in my head a screen looking like the original race selection.
Where all the races are shown, when you select one it has a short description of what the race is about and then additional information on the bonuses.
Yeah, something like that.
After all you're asking the players to make a choice and it needs to be an informed one -- this will of course be tricky as some players will be overwhelmed with small amounts of information while others will want very detailed information. The more this effects a players choices down the road the more they need to know.
As with every boardgame, one will have to learn the rules before.
With Mule , a new player will be able to play with the races standard (since food and energy will be available to all), but to use the bonusses effectivly, one will probably have to play a few games and then it becomes "known". Compare to learning the rules of how chess piece moves or what each piece of Archon does.
I was also sort of picturing that the order players get to pick shows up in the top right corner with a cursor showing who's currently selected and previous choices shown as well).
Of course this is one of the problems attaching the roles to a race. Races don't have much meaning to most players (or new players) where as a role of "Land Granter", "Miner" or "Farmer" might have much greater meaning (and could then have an icon/iconography made to help present a graphical meaning to each role (Something the races will never have). You could then cut down the total number of roles so that selection is more meaningful as well.
I attach a picture to show possible look of adavanced players hud, with race, icon or text as reminder of the bonus.
Having 5 players and only 7 roles means only 2 get left out. Which assuming the roles are all important makes the whole process more interesting.
Since computer can and needs to choose also, the Mechtron would be part of the selection, hence 8 minus 5 = 3.
The idea is to have smithore and crystite installation as specialty, also to not make it too hard to get one of these, have two species for each commodity. Hence 4 aliens are assigned 2xsmithore/2xcrystite.
Then food and energy are accessible to all aliens.
So those are not special. Food would then become mostly PLOT-dependent, meaning securing the water/riverplots early. So the other 4 aliens have rather big special bonusses, like:
Mechtron: if someone has NO food, he could stay in the game
Human: No bidding needed for the next hire phase, as he selects first by manipulating the computer (humans are smart).
Flapper: Big money bonus right in pockets
Gollumer: LAnd Auction or Land grant bonus (likely to get more land during round)
So these 4 have powerbonus, while the other 4 have specialty to install "powergoods".