Samsung Smartphones nowadays are good especially the Display, Battery, User Interface and Cameras but needs some improvement here and there which are mentioned as follows:
Starting with its pricing, phones should be launched at a cheaper price keeping your competitors and Public Demands in mind or at least, make the Build Quality even more better than your competitors.
Manufacture all phones with latest and best Qualcomm Snapdragon Processors even for Budget and Mid Range Phones and if not, at least make your own Exynos Processors as Smooth, Power Efficient and as Powerful as the Qualcomm Snapdragon Processors. If this too is not possible, then, at least optimize your UI in such a way that it can handle anything smoothly like how Apple does with their iPhones, the least Specifications at least on paper but a better performer in real world.
Also, there are a few bugs in the present One UI 3.0 Core and some of them were present earlier as well like the Ringtone can be set as per our choice but if we want to keep a particular song from the very beginning as the Ringtone, that is not possible as by default, it picks up automatically from the middle. There is no inbuilt Music App, Compass App, etc. given which you'll should have provided which is a must. Although, with the latest Update, the Compass is now inbuilt, but again, it's not a complete or full screen nor an App. Also, there are lot of minor bugs which are already mentioned by other Samsung Users. So, please fix all and also start providing all the must have and useful Apps built in, out of the box.
Last but not the least, please start providing Users the Charger inside the Box Package, for example, recently you'll decided to stop giving Chargers with the S20 series. Please stop this! Also, provide Good Quality Earphones, like the ones available with iPhone 5s, ear shaped, not in-ear. Also, make more Smartphones like your Galaxy M51 under Rs.20,000/- or under Rs.15000/- so that everyone can afford such good phones. Please give all the important features in Budget segment phones as well, like, Knox Security, Good Lock, etc. on all your Smartphones or stop the budget segment phones completely and bring in more A Series phones like the Galaxy A51 under Rs.20000/- with the latest and the best Qualcomm Snapdragon Processors like the 720, 730G, etc. with all the Security Features mentioned above because it's a must nowadays with the increasing number of Cyber Crime. And please improve the Fingerprint Sensor speed as well especially on the Galaxy A Series which have In-Display Fingerprint because it is slightly slow if compared with other Chinese brands.
Rest all is very good but you'll can make Excellent Smartphones of all kinds if you'll listen to the Public Demads, their Issues and rectify the same at the earliest. Then, no one can stop you'll from being the World No.1 and also the World's Best Smartphones, Good Luck!
I hope you'll would do the needful at the earliest.