Nice start on these. You are headed in the right direction. When you get your shapes worked out well, pay very close attention to the values. You want to match the values you see as closely as you can. It is important to be very honest about what you are seeing. try to put the accurate value down with each stroke as otherwise you end up having to fix things along the way and being accurate will save you time. Really take the time to observe and compare and choose the right value. If you are off, adjust it, don't keep working and come back to it. You are doing great...just need to focus in on value a little more.
btw....you can go over the hour mark and most do, you are right. Speed will come. The key is to balance the study quality and putting in time on analysis of the compositions so that you keep your mind on why the image was constructed the way it was and not just on how it was painted technically. The main reason for the shorter time frame suggestion is to keep folks from worrying about fingernails and eyelashes if the compositions are not being studied and the larger value, shape and edge patterns are left from the front of the mind. This study process pushes artists to work from general to specific and also to keep an eye on the compositional elements as said.
Take as much time as you need though...there is no rush.
John William Godward Study.
I noticed in this painting how he placed the woman in the middle of the painting, and her right arm also leads you to the head. The upper 3rd of the painting is all dark which helps to frame the her head and torso.
For this one I see a zig zag composition. From her head you follow the top of the couch to her hand, and then from the hand over to the chest. From the chest I go to her right arm down the dress then back up to the couch from the couch leg.