No. There are too many developments, too focussed on the area south of Shirley where roads are already too busy and there is no space to widen roads or provide new infrastructure. Traffic congestion on Dog Kennel Lane, Tanworth Lane and the surrounding area is already extremely bad at rush hours, and it is increasingly difficult to turn out of Tanworth Lane near the doctor's surgery due to the large volume of traffic coming from the new development in Dickens Heath. Proposed allocations 12 and 13 will exacerbate these problems significantly by putting an extra 1,450 houses on them - potentially an extra 2,900 cars, not to mention the extra 400 houses and 800 cars on the TRW site (plus any additional commuters if there is to be additional employment on that site). Even if new roads are built to access the Stratford Road, there are already traffic jams on the Stratford Road trying to get onto the M42, so putting extra traffic onto the Stratford Road is not going to resolve traffic problems, but will make them worse.
More of these sites should be focussed around the HS2 site if that is one of the main draws for new housing in Solihull. In particular, there are a number of sites marked as lower quality green belt land nearer the HS2 development that aren't being earmarked for development such as parcels of land RP18 and RP19 just north of Hampton in Arden on the Green Belt Assessment report 2016 (both plots of land only have a grading of 4, compared to RP69 and RP65 both graded as 6 but the latter have been earmarked for building allocations 12 and 13 even though they serve a better green belt purpose).
There are also a number of poorer quality greenbelt areas around Dorridge which would be more suitable for development. These areas would be closer to HS2, and are also closer to a better quality train-line than that in Shirley or Dickens Heath. Housing in Dorridge would provide commuters with access to around 72 trains per day to Birmingham (compared to only 45 on the Shirley line), and would also provide easy access to commute to London via either the existing Chiltern service, Birmingham International or the new HS2. In particular RP34 only has a grading of 3, and other sites are graded 4 or 5 (RP33, RP41, RP39, RP40, RP48, RP47, RP45). It would be preferable if you considered these sites to proposed allocations 12 or 13.
The added benefit of building around Dorridge is that Arden School is (I believe) being rebuilt on a new site, so this would be an ideal opportunity to rebuild a new, larger, fit for purpose school to cater for significantly higher numbers instead of trying to extend existing schools on their existing grounds.
There is a triangle of land near to proposed housing allocation 4, bounded by Houndsfield Lane, Tilehouse Lane and the railway line. This does not appear to have been included in plans, even though RP72 only has a green belt grading of 4 and there is already a proposed development near there, and it is significantly more convenient to access Whitlocks End railway station than proposed allocations 12 and 13. It may be that some housing could be put on here, or it may be that there's a plan to extend station car parking here.
There is also a number of green belt sites in the north of the borough within already built up areas around Kingshurst, Fordbridge etc. These are all poorly performing green belt areas, and the green belt strategic review has even highlighted some that do not perform their green belt functions at all. It would be preferable if these areas could be used. As they are amidst built up areas anyway, it would be possible to build at a higher density here, without the development being out of character for the area. (RPs 01, 02, 03, 79, 06, 08).
An area where a lot of space that has already been removed from the green belt which could be more efficiently used and should be considered before any new green belt building, is the huge car parking areas around the NEC, airport and station. Were some of these to be turned into multi-storey car parks, then a number could be released to build housing on, and these would provide significant brown-field sites and save removing further land from the green belt. These would also provide good access to the proposed new employment site north east of Land Rover.
In addition the density of housing being proposed seems to be very low. Both proposed allocations 12 and 13 seem to only be around 20 dwellings per hectare. To reduce the impact on the green belt, build higher density developments in fewer areas (particularly if one of the drivers for new housing is single person households). This was highlighted in the Government's Planning Policy Guidance note 3 suggesting a net density of 30-50 dwellings. If your intended figure of 36 dwellings per hectare is net (which I assume it must be), then it would be in keeping with the same to reduce the space used and build higher density developments, rather than only 20 dwellings per hectare. Look at alternatives for putting parking under houses to use less space. Consider terraces rather than semi-detached, or consider low rise flats. Higher density developments can be significantly more environmentally efficient than lower density developments, and can also allow residents of the new and existing developments to enjoy green belt countryside that hasn't been destroyed.
With regard specifically to proposed allocation 13 (south of Shirley), if this site were to be used (but I would prefer it if it wasn't), it would be preferable to build higher density further away from Stretton Road to provide a full field's gap (not just the narrow strip of bridleway and amenity land) between the estates to still allow for a significant band of open space. This land provides enormous intrinsic benefit to local residents and it would be a huge blow to the area for it to be built upon. It is possible to walk for over an hour on a circular route without having to go on more than a few metres of road. This provides good health and stress-relieving benefits for local people. This would be lost by developing this area. The fresh air would be replaced by polluted air from thousands of extra cars sitting in traffic jams, and would be detrimental to all impacted.
In addition, this area of grassland is important for drainage in the area. Building more tarmac and impermeable surfaces on this area is likely to have knock-on impacts for existing and future residents.
It is also an area that provides a large open space for wildlife and significant numbers of trees.