Not trying to be combative here, but the OP is pretty strong in his delivery and wording, and the OP hit so many topics relevant to me in a near opposite way I felt like I should respond with my own thoughts.
I originally had very little interest, and not a small amount of trepidation, with Secrets of magic as for me personally and my play group the magus and the summoner in particular were very disliked classes in terms of mechanics/design and negative impact at a table for a myriad of reasons not worth really delving into here(Though I am interested to hear if we were unique in this, as my understanding was that fairly universally summoner was pretty much THE singular class GM's didn't allow in home games and hated to see at a PFS table). I say this partly to refute the threads title, as a significant re-design of these two classes was NOT what we expected, but very much happy to see. In a way, seeing a simple copy/paste of these classes between editions would be a disservice to the design possibilities the new edition could give them and I am very happy to see this playtest.
I feel the unique new spell progression is a super interesting and honestly fairly elegant design direction. It may be just right, may need augmented with some king of cleric-esque font, maybe 2/2/2 or 3/3 works out better, but the DIRECTION of this spellcasting progression I love as a way to simulate focused or specialized limited casting.
Isn't saying these playtest versions are 'nothing like' their 1E versions a bit beside the point and odd? Of course these aren't mechanicaly alike, just the same as how the other core classes aren't mechanically alike to their 1E selves, its a new edition built from the ground up on a new framework...and is the point of the test not to compare 1E magi/summoners to 2E magi/summoners but instead to see how these new versions interact with the new 2E system and other 2E classes.
As to the OP's specific points..
1. Your first point is something the playtest magus can in fact do. Magi Cantrips exist, a magus can spellstrike using a spell of his highest known level EVERY SINGLE ROUND all day every day. Not that I agree with the idea that he should- A single, optimal 3 action routine that is always the correct choice regardless of the contexts of individual encounters is tactically boring and flat- in my opinion a bad design. The second assertion is trickier. As presented, a critical weapon strike DOES increase the result of the spell by 1 degree of success, which seems perfectly fine to me. The idea that magus should be critting more often than other classes, or that weapon/spell criticals were key to the theme of the class now or even in 1E I disagree with - the idea that 1E magus was a class Min/Max'd around abusing the mechanic of keened 15-20 weapon critical threat ranges to nova traited/free meta-magic enhanced shocking grasps and arcane marks is not something I would hope people would like to see moved forward. And even if you did, the suggestion that this design would be simple to balance in the frame work of 2E is neglecting to note that critical hit determination works nothing alike in the 2 systems on top of all the other possible concerns. Not liking the direction is one thing, but to wave away this design itteration as 'over-thinking' a 'simple' problem is frankly a little dismissivly rude.
2. You say you want a summoner which is a specialized class that uses a summoned creature....I see the eidolon feature and numerous 'evolution' tagged feats which alter and improve it which seems to fit that bill. I do not see a basis to your argument that the eidolon(a creature with its own statline which grows with you, and a statblock which you seem to suggest it is not), in order to fufill the theme or narrative purpose of the summoner class is required to be
*In any way related to the Animal companion feature - in fact, the less like a familiar or AC the eidolon is, the more specialized it would be to summoner, wouldn't it?
*have a seprate hit point pool
*Independent actions
This itteration is to me actually a very neat way to enhance the thematic link between the the eidolon and summoner while also elegantly dodging some of the more problematic issues with 'pet' classes ie unbalancingly high amounts of 'free' party hit points, avoiding the use of the minion trait while still reigning in the inherent power of multiple actors in a game tightly bound to action economy, providing interesting and class unique tactical movement and positioning concerns and options, keeping the flow of play/real world table time per player in check and others.
All in all my message would be I hope the playtest feedback will show that some of us at least like what we see here -the biggest step into new, unique, and interesting solutions to some complex problems we've seen yet this edition. Please hold your course allowing the themes, narrative space, and character concepts of previous classes to still flourish in 2E, while designing the best game you can now without feeling a need to keep the sacred cows of a previous game alive. Hopefully kinks are worked out, numbers are kiggled, major issues are addressed and we all get something better for having gone through this playtest.
