The two (gun safe and holster) are meaningfully divergent.
Holster:
In realistic scenarios, your ability to defend yourself will not be determined by the speed of your draw. More accurately, the speed of draw, in and of itself, is a vanishing detail when contrasted against your awareness, your presence of mind, your intestinal fortitude, and the strength of your practiced discipline. While one can demonstrate significant relative difference in draw time between an open-top holster and a level 3 retention holster, this difference disappears in actual practice. Choose your level of retention not based on the speed of draw, but on your analysis of risk and your level of risk aversion. Once you have chosen a holster, practice (ideally, with a Blue Gun, but at minimum with a personally-checked, unloaded pistol) slow, smooth draws regularly. Establish unshakeable confidence in your ability to bring your weapon to bear in defense. That's what will protect you in need.
Safe:
You can't use what you don't have. You must determine what degree of inaccessibility protects your family while you are at home without preventing you from accessing your pistol in need. The goals of protection from theft and accessibility in need are fundamentally antithetical. You will not achieve a balance between them, so don't give it a moment's thought. Protection from theft requires a degree of security that precludes urgent access. If you're away from home, either lock them in a properly-installed, bolted-down, side-protected safe, or don't bother locking them up at all, unless you have children, in which case you'll need objectively to gauge your children's discipline and maturity, with a minimum of trigger locks (in my opinion; some would argue a full safe is the minimum). If you're at home, the level of security you establish depends, again, on your objective evaluation of your family needs. Every step toward safety of your family is a step away from accessibility. No one can evaluate this for you, and guidelines would be misleading at best. All I can say is that even a four-digit, 10-value combination with repeatable values has only ten thousand possible combinations. Do you realize how bored kids can get at home alone? In my opinion, mechanical finger combination safes are an industry scam; they provide zero real security against a bored child. A quality biometric safe is the minimum I'd consider.