The more I think about it, the more a micro would be the most profitable/stress free machine to run if you were aiming only to do digger and driver day rate hires.
1. It's the cheapest.
2. It drinks bugger all diesel.
3. (Big one) You don't need a trailer. Just stick it in the back of the van or tipper. Towing a trailer around increases stress, time and diesel use and basically eats straight in to your bottom line. With a micro and van, you're more like a plumber just jumping in his van to go to a job.
4. The customer doesn't know the difference, and a modern 1.2t micro is not far off an old school 1.5t machine. And it's day rate, so who cares? Especially if you are spending most of the time running the power barrow to the front of the job anyway! Pro tip- tell the customer they can save on a labourer for a day if they want to drive the dumper. They love to play at dumper driver, you charge them £40 for the power barrow. Put your feet up and have a swig from the flask whilst they trudge out to the tip area, then look busy getting the bottom of the trench 'just so' when they round the corner on the return trip

5. No access will be too tight, or if it is, it was a spade job anyway,
6. When you end up doing other odd jobs such as paving if the digger work is quiet, a micro is a perfectly good machine to have on site to save you hours in labour. If it's your own machine, then for most garden landscaping jobs any loss of productivity is offset by the fact that it's yours and it can stay on site as long as needed. With a ripper tooth and a grab a micro makes plenty of garden tasks pleasant. When starting out, you will probably end up taking on these filler jobs so having a machine that can get almost anywhere will be a great help.
7. When needed, a larger machine is cheap to hire until you can justify your own.
I often think that's what I'd do if I had no yard and just a front drive. It's relaxing- no stress, just turn up with micro, spade and a laser. But I'll tell you something else too, if you buy new machines on a decent finance term (I do five years) then you don't need much work per month to pay for them. My micro costs me £230 a month and the 1.9t £280. So if they each go out a day a month then they are covered. My first new machine was the 1.7t, it's just been sold and replaced with a 1.9t. It cost me 14.5k, I sold it for 9k (could have held out for more, but did a deal with an honest bloke who gave a large deposit at the start of lockdown and was willing to wait till my new machine came when who knew what was gonna happen) New machine equivalent to old would have been 16.5k, I spunked on some extras to make it 19k. But take16.5k, -9k = 7.5k cost of ownership, over 4.5 years that's £1666 a year for a new machine under warranty, there when I needed it.
If you're coming in to some redundancy money, then I personally would keep that as working capital and get the machines that best match your work on finance. You've a long lead time anyway for new kit, so if you are serious you'd best start making enquiries soon.