You are trying to reopen lines that would be horrendously difficult to do so now, especially Wolves to Ryecroft, the Hampton in Arden line, Halesowen to Old Hill as well as trying to build a new line through some of the richest bits of South East Birmingham from the Lickey through Hollywood and Catherine de Barnes. Yet you have missed off the biggest one that is still a possible goer in Round Oak to Bescot, especially as you have suggested Lichfield to Brownhills.
How are you dealing with this new line at Longbridge, is it grade separated? same goes at Hampton in Arden and south of Solihull, you need to remember that released capacity from Hs2 will get filled again and not by trains in your proposal.
Your inner circle is a bit optimistic too, Arena station doesn't need to be at Monument Lane, the tunnel under the ICC is deliberately wide as the platforms were envisaged there. Your estimate to do the 15km loop with nine stations in 30 minutes is also very coarse! You cannot assume a 30 second dwell at these stations, so that takes 11 minutes (New St needs 3) and leaves you 19 minutes to start and stop for 15km. Your circle line trains will also be clashing with everything off the Cov corridor at Proof House, again anything released down the Coventry corridor will be filled immediately after HS2. The Vauxhall chord was never double.
Aston would be a nightmare with that level of service, one issue and it would collapse. Not sure moving the station away from where the access is currently much better solves anything.
Perry Barr is just being tarted up for the Commonwealth games, nothing more and you cannot get 3 tracks under the A34 without removing the platforms.
You want to expand Soho to Arena to 4 tracks, what are you doing from there to New St as you wont fit all the trains in. Some of the current Midlands Rail hub stuff is also pretty unlikely too.
Visionary, yes, feasible at lower than multiple billions, never.
Thanks for the feedback - never thought it would be easy

multiple billions seems like the right ballpark - Midlands Rail Hub budget is currently 1B for all the various bits of it.
Dotting around randomly..
Discounted Round Oak to Bescot from a passenger point of view because the trams are taking it over, which is 99% a done deal.
https://metroalliance.co.uk/projects/wednesbury-to-brierley-hill-extension/
(at 450M for 11km !) - they claim to be retaining "passive freight provision", although I'm not quite sure what that really means. I would speculate night time running of freight if the other smaller missing bits of track are filled back in.
Great to know that the tunnel under ICC is generous, that would make it easier to slot platforms in there.
At Perry Barr the little extra length of platform under the bridge (about 10m) - could be added on at the other end, and then platforms on both sides moved back - there is a massive redevelopment of the roads around there that could free up more land on north side of the line for platform / station use - and on the south side similar demolition of all the existing buildings on that corner.
CrossCity line does Blake street - new street 9 calling points 17km in 27-29min, so while I've been bit optimistic on the timing front, am I far out ? would 35 be more like it, or am I missing something that slows it down awfully ?
Aston currently has 8TPH calling at it - so this would increase it to 12 TPH. University is currently 10TPH + some extra through services at peak times.
Some of the current strategy seems to rely on digital signalling giving more capacity - what is the ultimate limit this can achieve ?
- and yes the ever present block of tunnel into New Street - again, does digital signalling give us anything here ?
Which bits of Midland Rail Hub are a stretch ? (tbh I've looked at their track proposal but not what they propose in terms of service frequencies on it)
Yes lots of grade separation of crossings where the ring meets the 'spokes', not considered each and every one in detail.
Longbridge is a sticky one, probably involving moving the station south, definitely some grade separation, possibly leave station where it is and longer tunnel option.