I had a 2012 Honda Unicorn before upgrading to the Duke 200. Also had one of the older Unicorns when I was in college. Friends have owned/own the P180, Hero Extreme, TVS Apache and Avenger and I've ridden them so I can talk about these.
Warning: I liked the Unicorn a lot so it might be a tad biased (or even more so)
1) Unicorn: You mentioned the new Unicorns are more plasticky and not as good as the original. Well spokes changed to alloys but otherwise it's the same. Newer ones look a little more premium IMHO. Still as bomb proof as the old ones. Service on time and forget about it. 17,5** KM in the year that I owned the new one and all I changed was the brake pad - twice. Everything else was regular service and oil change. It was my daily ride and I did numerous short trips on it, daily ride and a nearly 3500 km ride towards the end of 2012. Extremely comfortable both seating and ride quality through all that. I was always fresh and my mother loved sitting at the back and taking in the views.
The Unicorn I had in college was not as well taken care of. There was age related wear and tear as I bought it second hand but I once I got it fixed. Ran like a charm for 2 plus years. No regrets. Regular service as usual nothing more. College was in a coastal area and didn't have rust issues either ( except the number plate ).
For an older person the seating height and comfort are very good. Fun, fun ride. I'll always remember it fondly.
cons: A) Handling isn't the greatest. It's not as nimble as say an Apache but does what it's supposed to.
B) Cold start issues. I had to use a choke to start it, always. Rode it for like 500m with a choke and no issues after that.
C) It does feel a bit heavy but I liked that it was. This is personal I suppose. Obviously this contributes to handling as mentioned above.
D) Honda service wasn't up to the mark. It was up to me to ensure I got things done right - thankfully no major issues. Learned more about motorcycles so this was a plus I guess.
E) On the highway you'll find you want to go a little faster. 75-85 is the sweet spot. I've maintained 90-95 but the engine feels stressed. Very planted at all speeds though though you lose faith in the braking post 85 clicks.
2) P180: Enough power for the needs of most riders. It's not as unreliable as it's made out to be. Maintained well it'll run just fine for many years. Bajaj service is definitely a plus. Personally the seat is quite comfortable even if you don't sit as bolt upright as you do as on a Unicorn. Not as comfortable as the Unicorn but it's not the worst, can live with it. For your requirement here, the Unicorn tank rates higher but this should do too. VFM motorcycle in many ways.
- Definitely the better handler but it should be as it's far more performance oriented than the Unicorn.
- Short highway runs it's a great companion.
3) Apache: More committed seating opposition. Harsher engine than even the Pulsar. Superior handling to anything else listed here, this isn't even close. But for me as a commuter, the seating and engine vibes kill it right there especially for someone that's middle aged. I don't think this will be the most comfortable experience. Fun - yes, absolutely! Does come with ABS though. If not for that it'd be off my list. Also tires have to be upgraded, Zapper Q was good enough. You also get PSD's for them if I'm not wrong. Put that together with ABS and it'll be great if you can live with the seating and slightly harsher ride quality. Maybe this is hit and miss in terms of seating. You might have to ride it to know how you like it.
4) Avenger: Great highway cruiser, slightly heavy for city usage. Seating is comfortable, although the back seat feels awkward. I don't know if that's because I'm 6 feet plus. Braking is definitely the weakest of the lot mentioned here. Not my pick even if it's a great highway mile muncher. Every other bike does it too and has other advantages.
5) Extreme: The most plasticky and not as well put together of this set of bikes. I felt like it would just one fall away from coming apart (owners please excuse me here). Same engine as the Unicorn of course but doesn't feel as refined. It's tuned a little higher and altogether I just didn't feel too comfortable on it. Ride position is more or less the same, a little more committed than the Unicorn. On the plus side good maneuverability - feels more nimble to ride than all but the Apache.
What I haven't mentioned here is the GS150R. Definitely worth looking at, I don't know how many Suzuki service centers are around and how good they are. If you can find out about that might be worth picking up. It's more modern than the Unicorn for sure.
Verdict:
It's between the Unicorn, P180 and GS150R (maybe FZ-S, don't know about it) for me.
I've never met a person no matter how old who's turned down a bigger engine. So if there's no major issues of the back - the P180 would be a good pick up. It'll satisfy the rider for a long time to come in every possible way. It's powerful enough to not consider moving up and the seating comfort, ride quality are more than livable with.
If this feels too committed then I would go with the Unicorn. It'll last forever with minimal maintenance.
GS150R, FZ-S - I can't comment without experience. From the looks of it both have terrific parts quality and excellent reliability. No idea about ride details.
Hope that helps! My apologies for being verbose
