Solmyr, Demeer, and Aislin are cheaters (and/or) kamikazes; do the rest have a right to exist?

and one more thing, regarding the war with Scouts (this happens very often) - it will be very difficult to drive out a Scout-Solmyr with another Scout!

That's the whole point.
1. This change in the rules will make you think before rushing with a Fighter, and it will also make you afraid to leave Angels to build up.
2. The war with Scouts and Mages is also very interesting, and not everyone can do it... at least, there is so much more interest and complexity here than in a brawl with neutrals - depending on how skilled both opponents are.
Shakti with 180 Troglodytes will still be more promising than Solmyr without restrictions, because it's hard to cut down on resources with Solmyr, and Shakti can quickly rush through the secondary resource to the second week... Whether Solmyr can defend even in the capital is a big question, but if he can, then Shakti shouldn't have interfered.
In general, the most important thing is to introduce a rule for a random hero start.
And whether to unban all Tier 4 units is a more ambiguous question - it would be desirable to hold a test tournament or introduce it into the rules for one season with the caveat that, at the request of one of the opponents, the rule can be canceled... well, as for non-combat Mages, I don't think there's anything to think about - it's long overdue to unban them.