I live in Charminster, work in Boscombe and my parents live in Talbot Woods so I’m well placed to answer!
Charminster is a good area, not too far from the Talbot campus (though not as close as Winton), it’s an easy 20-30 mins walk to the town centre or the railway station too depending upon which part of Charminster you’re in. Lots of restaurants, bars etc…definitely livelier than than Winton (where I used to live). Parts of Charminster are very studenty though, I live in Hankinson Road and there’s loads of noise at night now that they’re back. Conversely, when I lived by Richmond Park on the other side of Charminster we had no student houses on our road.
West Howe has no redeeming factors, don’t move there. It’s also in the wrong location for you. Boscombe isn’t anywhere near as bad as people make out…sure The Crescent and Churchill Gardens are seriously dodgy, personally I think Springbourne is worse (I remember the night that there were 2 separate murders on the Holdenhurst Road within hours of each other). My girlfriend lives in Pokesdown within 5 minutes walk of Boscombe…it’s fine. It’s all vintage shops and nice cafes.
Boscombe itself has changed, whilst the surf reef has failed it did herald major investment…the promenade/pier looks great now and the likes of Urban Beach/Urban Reef, Reef Encounter, Koh Thai, Boscanova, The Crooked Book, etc have really improved the area. I’ve never had any trouble there and I work on arguably the worst road in Boscombe. However, Boscombe is beyond 30 mins walk of the university.
Your options are Winton or Charminster really. Talbot Woods is seriously expensive and there are hardly any flats there and Wallisdown is beyond dull and isn’t anywhere near Bournemouth or Poole town centres.