It's a weird upgrade in a way.
Its predecessor Ever Vigilant (1) is an entirely selfish card. Three assets, three resources saved, all yours. Very good value for a 1 XP card. But while sitting with 3 assets on hand and the resources to play them is doable, the step to 4 assets is a lot tougher. Spending three additional XP on the potential of one action and resource saved is a luxury most campaigns won't allow.
What we're really paying all that additional XP for is the multiplayer aspect. Which means that the type of player who wants Ever Vigilant (1) is not the person who wants Ever Vigilant (4). That's what makes it a weird upgrade. With (1) you're getting your own assets out quickly. With (4) you're steamrolling your party's tempo. Often instead of your own. It's however very effective at that. Slap it on a Stick to the Plan and the rest the investigators at the table will be doing puppy eyes at you every setup. And you'll realize that it's worth delaying your own setup so that the cluevers can hit the ground running.
TSK had a lot of multiplayer focused cards for Guardians (which I liked as a direction). But while I think that this card is very strong as a multiplayer card, that is not what its predecessor was about. Another card that would have fit this design space better is Teamwork. A Teamwork (2) that gave every investigator at the location a to play an asset with a lower resource cost would have been great, followed the theme of the card, and helped with its original purpose.