Suggested

Weaken DRS

At high levels DRS is simply way too powerful. Getting DRS any given lap can cut your lap time by a second or more. This means a significantly faster car can actually lose time to the cars ahead if the cars ahead are all running in a group. The races feel like a guessing game trying to get DRS as many times as possible throughout the race rather than actually coming up with a strategy that is as fast as possible. For example, if a small group of cars all run the same strategy that should be 10+ seconds slower over the race than another car’s strategy, but the faster car doesn’t have anyone to DRS with, then they will almost certainly finish well behind the group of cars that didn’t have as fast of a strategy. In real life a DRS train is limited to running at most as fast as the car leading it, and you don’t see 3+ cars swapping positions through the DRS Zone every lap. Right now racing feels like an open-wheel Daytona, where losing the draft (DRS) of the pack costs you a ton of time and effectively ends any opportunity of winning the race or even finishing well. My suggestion is to weaken DRS in general, forcing faster cars to close the gap on slower cars before making their move (currently you can overtake from over a second back on some tracks with help from a lap car). Idk what the speed in KPH/MPH would need to be, but you should really need to be within half a second of the car in front to even consider making a move. I understand this would be difficult to do given the need for 20 different levels of DRS, but I think figuring it out could make for better, more strategic racing.

My unpopular opinion: this is the spirit of the game. Leading car won't escape from opponents because developers want that you fight. It's up to you using boost to be in the best place. When I have a faster car I use a bit of boost at the beginning of a long straight where there is no DRS. I will overtake enough cars to be in the first places of the group. I will never escape from the group because I want the DRS advantage and I will use my boost to get more DRS. If you are faster you will close any gap caused by previous DRS and if you don't, you should use boost.

Absolutely agree with the post. The strategy of DRS group is too much strong if another one is on another strategy without any car exchanging DRS. DRS is really broken like in Spain where you get 2s more. Related to this issue I would add more bit dirty air 

IMO, drs is not the issue. It's finding the perfect balance for each track which is almost impossible. You can't just pick drs, say weaken it and expect to see breaks (perfect example is re-fueling allowed Spa) which basically still plays more or less like a train despite having a very weak drs.

Talking about lighter cars, they can surely break away and run solo (in no-refueling leagues) even on tracks with massive trains so basically I just think it's different strategies for different aspects of the game. There is no one shoe fits all.