When you have a strong core you can pretty much do anything you want exercise wise. Although back exercises aren't the easiest to do, they are the most important if you want to be able to lift well and exercise without hurting yourself. Plus, plenty of back exercises for men also help to incorporate lots of muscle groups so it's a win win, because you only strengthen your core, but gain muscle elsewhere.
Whatever the type of deadlift you're attempting, just by doing them at all you are strengthening your core. The more you (safely) do deadlifts, the more weight you will be able to move in future sessions. The Dumbbell Romanian Deadlift is particularly good for your back and also promotes hamstring flexibility which helps alleviate back pain.
Deadlifts are also an important exercise to fit into your daily routine because they enable the body to release testosterone which is an important hormone for muscle building.
A big back equals the ability to do a high number of pull-ups without suffering from as much pain and burn throughout your workout routine. Both pull ups and chin ups build your core muscles and target plenty of other areas, so they are definitely always well worth doing.
Put the effort into these exercises as well as modified versions of them, and expect to build core strength in no time. Change it up by;
Back extensions are great for a wide range of muscle groups including the glutes and hamstrings. You should always be in neutral spine and nothing should be hyperextended during the exercise.
Back extensions can be overloaded using different gym equipment. Change it up by;
Seated rows will always strengthen the back if they are done properly. Bad gym habits (chin tucking etc...) will render the exercise useless, so in order to see results, you must always perform these maintaining excellent form.
Again these must be done properly in order to get good results. You should have a neutral spine and your torso should be parallel, not upright or with an arched back.
By working on having a strong core, you will protect your body from a huge variety of avoidable injuries. You will also provide yourself with the tools to reach your lifting potential. Big muscles don't actually always indicate strength, especially core strength. It does pay to focus on the smaller muscles that help you stay stable and balanced, especially if you're planning on improving your form long term.