To be fair, 71% WR is overall. My solo WR is lower than that at ~67%. Div'ing with good players makes a difference. And I'd still consider myself a casual player in the sense that I don't actively participate in CBs, KotS, etcetera. The strategies used in Randoms are completely different than those used in more competitive formats.
With that said, game balance SHOULD account for skill floors and skill ceilings. Which is why it's important to get feedback from all skill levels of the community. What an average player deems OP might not be deemed as such by more skilled players and vice versa. Which is ultimately why there's so much debate on hot-topics like radar. Some don't think it's an issue. Some do. Others play around the mechanic just fine but don't think it's good for the game.
I think efforts could be made by WG to better communicate the capabilities of certain ships in game. Perhaps via an indicator stating which ships can mount radar. My guess is that the majority of players in this game don't memorize which ships have radar or what their range/duration is. For people newer to the game, audio prompts telling you that you're being radared could be useful. Too many times I see players sit in their smoke, get radared, then killed and they subsequently ask, "How could you see me in my smoke!?". I suspect there are also players that have thousands of games played but STILL haven't studied those little details. Prompts like this could be useful for them too. Although people might say this is dumbing the game down because the information is already there if you care to look for it.
My OPINION is that radar needs to exist in some form. Even if it were as simple as showing the DD on the mini-map, but not a rendered 3D model... just an example. However, if changes like that were made, other aspects of it would probably need to be buffed to compensate.