Keren has done an admirable job of describing and explaining your heifers. I would just add that it appears to me that the dams of these heifers are more of the "Dairy Type" than "Beef Type". They are leggy, thin boned, long-faced, shallow and not "blocky" as BEEF cattle should be.
I would suggest that you acquire some sale catalogs of beef cattle sales from here in the States, and just look, and look, and look at the pictures, and read about the individual cattle themselves. Pretty soon, your brain will recognize what a BEEF animal really is - from its hooves to the head to the top line to the desirable meat areas of its body. It will implant and "image" in your mind that you will automatically compare to other cattle that you see, and you will just - - Know - - that what you look at either has good phenotype - or it doesn't!
Takes work. Takes time. Takes determination. Takes study. When you can say to yourself "Hey! I think I've got it!" - you are on the road to NOT being Barn blind. You have to be able to look at your OWN animals and say "That looks good!" But, more importantly, you must be able to say " That is lousy!"
As a quick study right now, take the two pictures of these heifers and place them side by side. Then quickly look back and forth, back and forth, from one to the other - to the other - and mentally compare the differences between them. Pretty soon you will be able to do that with live animals, and the differences will jump out at you and yell at you. After you have implanted the desirable images of GOOD cattle in your mind, you will be able to discern what is acceptable and what is NOT acceptable.
Have a GOOD time! And think POSITIVELY! If you think that you can't - you can't. If you KNOW that you can - you WILL!
DOC HARRIS