Good range of Engines
Petrol 1.6 / 1.8 / 2.0 TS, 2.5 V6, 3.2 GTA
Diesel 1.9 8v and 16v / 2.4 10v and 20v
Dated Interior on some of the older ones (Might be before 2002?)
Doesn't affect all non face lift types. However if it was me I'd try get a face lift 1.8 TS.
Sportswagon practical. Think of a slightly larger hatchback. But will be heavier.
Personally if you can stretch to the 1.8. 140hp, No balance shafts and personally having driven all the TS and V6 petrols the 1.8 is a good compromise (Would be even better if matched to the 1.6 gearbox).
Running costs of all the TS engines mpg wise is the same 1-2mpg average difference.
Poorer Engine Range
Petrol 1.6 / 2.0 TS and 3.2 GTA
Diesel 1.9 8v and 16v
Interior all newer and uses canbus system so a bit more on the modern scale.
However underneath virtually identical. So you get the same issues with both 156 and 147
Not sure if the seats drop on the 156 but I'd probably say the 147 is more practical if you can't drop the seats (Unless its the estate as they do drop).
I think the 1.6 TS in turismo spec 156 is the lightest due to less systems. No leather etc. Lighter base than the 147. But not enough to worry about.
If I had to pick again I'd pick a 1.8 TS sportswagon out the TS range.
Or 2.5 V6 Sportswagon. Manual would be my ideal. But they are like rocking horse poop.
I love the 147 and its been with me a while but the boot is an odd shape. The turrets for rear suspension are weird.
Put it in context. Your Punto boot will be far better than both unless its an estate. I know because I had a Punto (5 door)
Even a 1.6 will feel quick compared to what you are currently driving. But be ready for the fact they do circa low 30's mpg. Where as the 1.2 8v 60hp punto is closer to 40mpg.
Also get ready for a shock on Tax. They are all virtually the same bar the diesels @ £250+
From Experience though. Go for the 1.8 or 2.0. Insurance won't be that much more same as running costs.
Alfa 166 2.0 Twinnie - LPG and a few trick performance parts