Is the score really important?

Unfortunately, yes. Any customer or generally any WoW player can confirm that you cannot go very far without a high score. You will not be invited and you will have a frustrating experience whenever looking for a team to play Mythic+ content with.

While it is possible to slowly raise your score by banging your head against this invisible wall, a boost will help you get your score super high within a week, and avoid any problem for the future!

Check the fraction of your character by the following site. 

https://raider.io/mythic-plus-rankings/season-bfa-2/all/world/leaderboards