This feedback is based on individual experience (just playing from time to time, so no long time experience really) and also influenced by the oppinion of some of my friends. I also differenciate between public/for fun and competitive aspects. Much of this is well known⌠but well I just feel the urge 
Positives:
Mercs - Allways liked them, still like them. They really give us a chance to dive into a specific play style. For casual jump into the game it seems to help that there aren´t any class specific objecitves etc. And while this actually can help out the variety of mercs who are being played and give us more freedom in what we play, it also can increase the stacking - since you simply don´t need certain classes. Still, overall I enjoy picking up different mercs, and look forward to add more of them to my arsenal (or whatever it is called) and hope that there is more to come!
Gunplay - Well I like it. It emphasises movement, it is fast, it is deadly if you are accurate. Feels great when you hit them âbingsâ. But allow us to give it a custom sound pls
UI - I haven´t tested it much, it seems bit laggy and maybe there are bugs and still some flaws. But I really enjoyed just starting up the game right clicking and joining friends who are playing in game. Don´t knolw for how long this has been in the game all ready, but it was needed for sure!
Negatives:
Maps: They are beginner friendly. I admit that. But they are mostly trash if it comes to long time motivation (that´s why I only play DB VERY occasionally). So even in a casual environment, there needs work to be done. On a competitive level, most of them are still going to be a disaster. I understand this is contrary to being beginner friendly, but you could do both, and unlock more advanced maps with the players increasing level. I also want to see a section for custom maps. Otherwise it will take forever until a decent map pool is going to be there.
PS: I don´t think I have played all the maps on this build, maybe some improvements have been done. But knowing the old maps, small improvements want change too much on this opinion.
Missing âclassesâ: For pub I have no concerns. It focuses mainly on competitive play. I can´t tell yet how the proficiency actually works out for the objectives. It is very plausible that they are enough, especially if ballanced properly, to give the game sufficient depth in this tactical aspect. Individuals in game just have to be different in importance for there team. It must be worth or even needed to play defensive with some mercs, while it must be a valid strategy for the enemy team to exploit teams that don´t play well around there crucial roles. Picking up allies tho, seems to be too much BUT that doesn´t have to be true. We will have to see how all this roles out in a competitive environment. It is in the negative section, because in my eyes this needs to be heavily tweaked and adjusted to help the game get some tactical depth. You could call it a make or break factor.
Movement (very personal):
I still want to go faster when moving straight line. Fights are quiet nice paced on various distances allready, that´s fine but when I am going out of the spawn I want to have some impact on the speed I am going at and I want it to be skillful. Admittedly that´s not that big of an factor tho 
Performance - For me the FPS performance seems to have increased⌠Not too sure tho^^. However the drops are still massive. Please you can do that better 
Summary:
- ) Please work on the maps! Give us chances to contribute some. Lay them out in a way, where they are challenging and give a lot of tactical options to play with and implement them in a noobfriendly way!
-) Balance the proficiencies for a competitive environment (maybe in a unique build for competitive?) or remove some of them so that certain characters are crucial for a teams success adding a lot of tactical depth into the game.
-) Maybe think about a way to implement a way of movement that you can do straight out of the spawn, that doesn´t change the gun fight. This could be done by disabling âfasterâ movements while being shot. This right now isn´t that much of an importance, but it will also free you up on map design if people are able to move faster!
-) Performance. Yeah, you know that I am sure
PS: I haven´t noticed the balance of mercs etc. since it´s a waist of time to ballance them in a still relatively new build, and without a whole lot of sufficient data. Also it´s a thing I am least worried at, at the momentâŚ
cheers,
onYn