If you suspect you have battery issues then you can get an OBD Dongle for your phone paired with the Leafspy app to get an accurate look at your battery pack health. It will show the amount of capacity (health) remaining as a percentage, as well as showing if any of the individual cells are weak.
If you have a 40kWh LEAF as I suspect you do, the 153 Mile range is a best case guess based on how you have been driving recently, as well as being from 100% down to zero - Which you obviously wouldn't be going that low as you need to plan where to plug in.
75 miles to go from 100% down to lets say 25% sounds about right in terms of range on the motorway if you're going at 70mph, using air conditioning, accelerating fairly quickly, and especially if you have a bit of wind and rain against you. As the weather worsens and we approach winter this will get very noticeably worse too.
Changing your driving style, running on motorways at around 60 while keeping a safe distance behind a HGV, planning ahead for accelerating and braking, pre-heating/cooling your car while plugged in before setting off for a journey, and picking a sensible comfortable temperature for climate controls will all be helpful with your range to maximise it.
Another suggestion is to make sure you are using AC charging to let your car charge all the way to 100% and keep going until it shuts itself off at least once a month if you don't already. This cell balancing is important to keep your battery healthy and give as much range as possible. Signs of a cell imbalance or weakness include the range dropping faster and faster as you get lower on remaining charge levels.