Yes. Lower your expectations.
CornishX are "purpose built" to be a highly efficient, extremely fast growing bird for meat production. Those traits are emphasized even to the detriment of the bird's longevity and heartiness. Commercial layers (like the various Sex Link and certain leghorn lines) have been "purpose built" to be small body mass (because they cost less to feed) frequent and early large egg producers, again at the expense of longevity - most are famed for reproductive problems in year 3+, sometimes sooner), and for significant drops in egg production after first adult molt - which is why they often become dog food, etc around that time in commercial practice.
As long as either of those are the points against which you measure, you are guaranteed disappointment.
A good dual purpose bird, if you will forgive the analogy, is a Chevy Impala Sedan. It looks like every other sedan on the road. It doesn't get great fuel economy, it doesn't accelerate like a shot, doesn't stick corners like its glued to them, doesn't brake on a dime, isn't particularly spacious or posh.
What it does do is reliably get you from place to place. Solidly "middle of pack".
What we see from hatchery stock (and a bunch of breeder stock too!) is largely "dual purpose" breeds which favor egg laying at the expense of meat production - that's the way the backyard market has tended for the last several decades. There has also been a distinct trend towards improved free ranging ability as a way to distinguish from battery raised birds.
Free rangers consume less feed, great, but are more active. That's a more flavorful, lower weight, less tender bird - which you are culling at greater age in an effort to make it what it isn't - a "CX-sized bird for the table". There has been some targetted and successful effort at putting meat back on those bones - among some breeders - but also a lot of hatchery birds of no particular exceptionalism. The "Ranger" term is as much marketting as a solid indicator of charateristics in your poultry purchase. Even going with a heritage isn't a guarantee - the Wyandotte was developed a bit more than a 100 years ago, an attempt to get something like Brahma weight, w/o the Brahma late... Its a bird that lays medium eggs maybe 3 days out of 5, is cold hearty, doesn't start laying till 5 or 6 months, and probably weighs less than 4.5# as a cockerel at week 16. And yet, it was a dual-purpose "improvement" upon what came before.
Our tastes as humans have changed a lot, too. What we now consider "tender" would be mushy by past standards, we like less gaminess and less tooth in our meals, together with greater protein.
My recommend is that you consider how much space you have, how large a flock you can reasonably support, and how many eggs you want (on average) each week. Think about your incubator. Then plan around all those things. I incubate 12 eggs every 3 weeks +/-. Assuming a 75% hatch rate, and a 50/50 split male/female I'm looking at 12 birds a month, give or take. That means I can cull six males a month for the table, if desired, while maintaining flock size and gorwing up hens for replacing those aging out. During the same month, I can, in theory, take an equal number of hens (all from 15+ months ago) who are coming into adult molt, and are now suitable only for stew, stock, or sausage. That's not enough protein for my wife and I to support our diet, but its a goodly amount.
Something like 40% of my flock is under productive age, in the process of growing up, at any given time. Either hens not yet at start of lay, or cockerels putting on table weight. Even free ranging, we have a bill around $120/month for near 500# of feed from alocal mill. I offset that with egg sales, and credit myself the costs of equivalent proteins I'm not buying at the supermarket. On that basis, its barely break even.
Now, look to my flock size in my signature. I actually have
a culling project to select over time for the best "dual purpose" bird for my piece of land and management style. As expected, its going very slowly, though I have had a few early successes, I've not yet been able to capitalize on them. I've also had some major setbacks. You have to plan for those too.
Your advantage over my starting out is that things have settled down, you have choice in birds. I suggest you use some charts, like
this one,
this one,
this one. You are looking for a breed laying large eggs, at least 260 year, early maturing to moderately early maturing, that eventually produces an adult hen over 5.5#. You want to consider your climate as well.
Once you have selected a few breeds that you think will work for you, use the Breed forums to ask about those particularly - experiences of others, best breeders/lines for those birds, etc and dial your selections in further.
What you then expect is an egg two days out of three, from hens that start laying around 20-24 weeks (18-22 if you are lucky), with cockerels in the 4.5 - 5.5# weight range around 16 weeks. None of which is worthy of writing home about - but it is achievable and sustainable. After that, you do as I do - selectively cull. Eat your smallest males, breeding the size up. Mark the hens who come into production the slowest, and don't incubate their eggs. Don't incubate small eggs.
Basically, the underperformers are consumed, the best become the "seed stock" for the next generation. Always have one productive roo and a back up, plan on replacing your top roo annually to keep some diversity in the lines.
Hope that helps.