Let’s say you want a specific 5* character in Classic. Your odds in 3 weeks, when Thor enters Classics and there are 20 5’s in there, will be around 0.75% of getting, say, Thor. That’s about 133 pulls to get, with even distribution, one of each Classic 5. Getting more covers gets into statistics and it starts getting more likely that you get some of one 5 over another, since even distribution is a very unlikely scenario. Anyway, 133 pulls is 2660 CP. Now, you might end up with 2-3 of one character and 0 of others (and probably would) so who knows where luck takes you there.
Now let’s say you want 300 pulls in the Latest store, which is recognized as the best way to move to the 5* tier, and probably gets you 3 13 cover 5’s. That’s 7500 CP, but you will have LTs as well to make up some of that CP. But, if you took that 7500 CP to Classics you would probably have, on average, 0-5 covers for all 20 5’s which is basically worthless. My estimate of earning about 25CP a day means its about 150 days / 5 months to get 7500 CP. I don’t got to 1200, so if you do that, you can drop your time by about a month, I guess. Either way, the mountain you are trying to climb is impossible if you dump CP into Classics unless you are going to dramatically increase your CP with spending.
The odds of getting a specific 5* in Latest is 5%. The odds of getting a specific Latest 4* from a pull is 3.54%. The odds of getting a specific Vintage 4* from a pull (currently, with 60 4*'s in tokens) is 0.885%. (Luckily, there are other avenues for getting 4* covers now.) The Latest store provides, no question, the best bang for your CP buck. And cover swaps are a thing in Latest and make it a lot easier for the average player to finish a 5* vs cursed RNG getting in your way in Classics.
The sad fact is that the Classic 5’s that aren’t significantly covered are probably locked away by dilution for players. Feeders can help if you are lucky, but even there, getting someone to give you all 6 covers will take a lot of focus on one 4* as a bonus hero.
The 5’s are the carrot. The recent actions of the devs make them a little more attainable, but there is still a huge hurdle in getting a Classic 5 covered, and I really can’t see how someone can start from 0 covers now and get there until, perhaps someday, there is a 5* cover in placement or progression. But making it too easy makes 6*'s something of the next carrot, and I believe the game will shut down before a 6* is introduced.