Good to hear you are putting another nice ride that will match anything currently available for all round usefulness, back to rights Rabbit. My neighbour rides one albeit not a mixte. He has been using it for commuting/social transport and leisure for over a year now. He has told me on more than one occasion that he is so pleased he allowed me to persuade him to spend 50 or 60 quid on it - which I used to do it up. He says it has slashed the time and cost of his commuting at the same time as making him independent of transport services and being able to go visiting as he pleases. He also says he feels much fitter as a result and can get to places for his rock climbing that were previously pretty inaccessible to him. Anyway point is well worth it, in so many different ways. One thing he did buy of his own volition was a very good lock for it - as he realised what a valuable machine it is to him.
Freewheel removing is often a thing that those not familiar with it find difficult. So for what it is worth and to any others interested; Having obtained the use of the correct extractor tool - most types are quite cheaply and easily available - Most importantly it must be engaged properly. To do this take off the axle nut. On some you also need to remove the cone locknut and a wide spacer which stops the tool engaging. This sometimes necessitates loosening the cones on the other side of the wheel, so that you can draw the axle through enough to get a spanner on the "freewheel" side ones - replace the axle by running the cones up finger tight. Fit the extractor and run the axle nut up to it, just about finger tight, to keep it firmly located. Grip it so that the wheel is horizontal in a firmly fastened vice. With the tyre fitted and at least partly inflated - turn the wheel, in the same direction that the chain pulls it. Loosen freewheel. Undo the axle nut and run the freewheel off.
That method undoes them easily and prevents any sideways forces that can buckle the wheel.
Another thing people often have a problem with is undoing the Bottom bracket cup that is under the chainring (RH side). - if you do not have a big enough spanner to fit it very firmly and well - using a vice in the same way as for the freewheel is a good method. They do not have to be wrenched up tight on replacement - just firmly is amply sufficient. All the parts to replace them with original are easily available; these are the most long lasting, cheap and reliable type of BB. SJS cycles have all you need.
Perhaps worth considering is that while at this point you have the opportunity to fit a gear range that can out gun anything on the road that comes from a shop, in both high and low directions (except my bike!). By fitting a longer axle to the BB and using a triple with a custom range of chainrings 24- 39-52 for a suggestion. You need to use a MTB wide range derailleur. On the rear wheel a freewheel/cassette from 13-32 (as a suggestion) and again using a MTB wide range derailleur. The derailleurs can easily be obtained from BSO's in skips and such like - some of them are actually quite good quality.
I don't know if anyone will find that useful - but it is my tuppence worth.