What Can Be Done to Improve the Appearance of my Nose?

Although it is difficult to tell from the single posted picture, rhinoplasties can be performed without feminizing a nose.  By removing the dorsal hump through a series of maneuvers to refine it, this will typically not feminize the nose.  Judging by your picture, minimal to no top work would be advisable.

Male rhinoplasty should be addressed differently than rhinoplasty in a female.  The aesthetically pleasing proportions and measurements in a female nose are different than those of the male.  This is always taken into consideration when performing male rhinoplasty and should be addressed by your surgeon prior to the procedure.  Keeping a strong profile and avoiding overrotation of the tip are essential aspects amongst many when performing male rhinoplasty. 

Yes, this is what good surgeons do. Look at the work of experienced rhinoplasty surgeons to find one that does refinement of male noses without feminizing them. Your bump can be removed without a "scooped" look and the tip made less bulbous without being "pinched". 

When rhinoplasty is performed it is usually to take a hump off of the nose, narrow the nasal bones, reduce the bulbousness of the tip, and sometimes narrow the nostrils. A septoplasty is performed to improve airflow dynamics through the nose after patients have failed medical therapy for better breathing. It is important not to make a male nose look too feminine.

Other photo view would be helpful. If you have a small dorsal hump, then this can be corrected.  A deviated septum can also be straightened but I have never seen a perfectly straight nose even after surgery.

This can be done by a very experienced rhinoplasty surgeon. I would file the dorsal hump and correct the deviation. I doubt I would refine the tip. Best of luck from MIAMI Dr. B

Regarding: "have a small dorsal hump and slightly deviated septum, ... I am also wondering whether to improve these defects the surgeon would make my look to feminine? would a more masculine nose be achievable?".

To render judgment on a nose one would need more than a single rotated frontal view. Ideally, a true frontal, bilateral side views, bilateral obliques and  an inferior, worm's eye view are a lot more helpful.

In your case you appear to have a long nose with a small hump with a narrow dorsum ending in a large somewhat droopy tip (due to very large lower lateral cartilages) and possibly a visible septum (Columella) on side view. There is no reason why your nose surgeon could not correct these WITHOUT rendering your nose feminine.

Seek out an experienced nose surgeon and discuss your concerns with him. Your rhinoplasty should be individualized to your wishes.

A good rhinoplasty surgeon will remove your small dorsal hump and, if necessary and desired,  improve   tip definition while maintaining a strong masculine nose. Subtle changes will make a significant difference.