First of all, we cannot predict resale value at this point most of these models are new (maybe not the Raize) so we do not yet know what kind of issues/trends to expect with these. Usually due to various import regulations and tax structures changing, resale value of cars increase - however if they do remain constant then obviously you will lose a bit of resale value when you buy a brand new car - but this is Sri Lanka so that is a very remote possibility.
The City RS Drives well - it squeezes a lot out of a 1L engine. Decently appointed. A sedan in an age of wanna-be hatchbacks. (deserves some respect) I do have a gripe with the interior materials though. The seats have a Mahendra/Boleroesque feel to it mostly due to the material used - it just feels a tad cheap.
I don't see a 'massive' hit on resale value. Honda's sell well here - the GP1's had their oil burn issues, the GP5/Grace/Vezel unholy trinity had recurring dual clutch issues, the Civic FK6 with it's timing-belt-turbo combo issue, and yet none of them have taken 'massive' resale value hits.
Fronx - I'm yet to drive or be driven in one but at first glance it appears to be rather compact and snug, and same with the sonet.
The Raize, as you mentioned is quite spartan - the variant that TL is offering.
Wouldn't 15.5 Mn fetch you a recon 2023 ish JDM Yaris Cross? The other alternative is the 1.0L Turbo Nissan Almera which goes for around 14 Mn I think?
Badge impression aside, It would not be in the same league as the other options. It costs way less so it's a more value for money option but the looks are not everyone's cup of tea, and while most of the 1.0 L options discussed were turbo charged the Bezza comes with a NA 1L engine - OP might find it quite sluggish compared to the fronxes and the cities.
Too early to tell specifically with regard to the City but Honda did use this with the tenth gen civic 1L variant so can be expected. As i mentioned earlier these Honda P10 engines make a crazy amount of power from 1L engines as a result these engines run hot a lot -the problem is the belts are also located inside the engine lubricated by oil. Oil that gets very hot and in turn the belts start disintegrating around the 100,000 km mark. This will lead to particle build up in the oil, cause clogging and affect the engine including the turbo. Depending on how frequent the oil changes are done and how you run can change this a bit - for instance I know a guy who had to replace this belt at 200,000 km on a Civic and then there are those who has to do it at 80,000 Km. But the risk is there. As of now the belt will cost around 125,000/- and replacement cost will vary per garage/mechanic. The agent will quote an arm and a leg.
These would NOT be straightforward warranties - not quite scams but you will have a tough time claiming them. If you're concerned about warranties I think a grey import is not your cup of tea - you might be better off with a fronx.