People say that Naruto is weak without Kurama and that he is high jonin level at best. You are underestimating him too much. In sage mode alone, he was able to defeat the third raikage and Kurama. Also, he is much stronger than Kakashi in sage mode. Kakashi actually stated that Naruto surpassed him when he learned rasenshuriken. In sage mode, Naruto can make multiple and larger rasenshurikens as well as rasengans. Let's not forget frog kata style. Do you remember that invisible punch that Naruto did against Pain? That attack would totally wreck many people. Also, Naruto is stronger than Tsunade and Utakata in sage mode. How many paths of pain do you think Tsunade would have been able to beat? As for Utakata, he was only able to destroy about one or two Pains. Naruto is also still the strongest in Konoha 11 with sage mode alone. Finally, Naruto is even stronger than Jiraiya with sage mode. Jiraiya struggled against 3 pains and needed the help of the two frogs while Naruto quickly beat up to 5 of them before being pinned down by the Deva path and seeing Hinata get stabbed. This was before Naruto got even better with sage mode.
Do you see now? Naruto is not weak without Kurama! He was even able to help against Madara in sage mode (unlike those other random shinobi). In the third shippuden movie, Naruto even beat Gaara in his base state! If Kurama gets extracted and Naruto survives, he will still be at least mid to high kage level. Yes he would be weaker than he is now, but he would still be nowhere near weak in general. In case you are wondering, no I did not include anything about Sasuke in my analysis (so I am not trying to start a Naruto without Kurama vs Sasuke war).
Ps. Why do people criticize Naruto about using Kurama and say that he always depends on Kurama? He just got BM that day (in the manga time). He just got KCM the previous day (and that mode technically belongs to Naruto. He can use it without Kurama's cooperation). Before that, Naruto mainly just stuck to base state and sage mode (except when he got really mad). He single handedly beat Kakashi without Kurama's help (yes I know he apparently got those red eyes at one point, but that didn't really do anything).
Finally, nobody ever criticizes Bee or any other jinchuuriki about this issue (and Bee uses Gyuki all the time)! They only criticise Naruto. Why is that?