Mega Man: The Wily Wars is an interesting collection of 16-bit remakes of the first three Mega Man games, featuring an equal amount of improvements and bad changes.

The most obvious change are the graphics and they are a mixed bag for me. On one hand, there are some really nice backgrounds that the first Mega Man in particular benefits from, but then there are the character and enemy sprites, which I didn't like nearly as much as the Iconic NES counterparts. Worst of all are the larger enemies, which have weird and ugly shading.

Gameplay is mostly identical to the originals, however there are occasional small changes, some of which I liked and some of which I didn't.
For example, the super arm's throwing arc was changed so that when fighting Cutman I would throw the rocks directly over his head, which led to me finding out that for some reason Cutman no longer takes extra damage from the buster which was a little annoying.
Better are changes for some of the more unfair or difficult to dodge bosses like Fire Man or Wood Man and the biggest positive of this game was how much more forgiving the Doc Robot stages in Mega Man 3 are.
But I think it's a missed opportunity for them to not change some of the more obvious shortcomings, like the parts where you need a certain weapon to progress, but when you run out of energy you have to farm or get a Game Over.
Just place some respawning weapon energy at these points and it would make it so much better.

Then there's the new Wily Tower mode, which was a nice and unexpected bonus for beating all three games and allows you to choose a set of weapons between all of them for a series of new levels that combine elements from across the three games.
The weapon balance could be better tho as I obviously chose the metal blade for each level and they could have made it so that more enemies from 1 and 3 are resitent against it, but that wasn't the case.
Over all nothing to crazy but it was enjoyable.

As a fan of the first three Mega Man games, I think its worth playing through Wily Wars at least once, but I prefer the originals.

The pain continues. Like X5, X6 isn't a good time, but at least it's a little bit better.

First, there are almost no interruptions from Alia and second, it doesn't take forever to defeat (most of) the bosses.
Still, the level design is bland and this time full of enemies and projectiles, so you can't walk two pixels without getting hit by something.

The damage you take isn't high, at least not on Normal which I only played on for now, but it just feels bad because I just played through everything without caring.
It didn't help that a Game Over no longer means anything and you don't lose your checkpoint after you get one, which to be fair makes the experience a lot more bearable.

Then there is a hidden boss that can only be hurt with a specific weapon and is therefore impossible to defeat if you find him without it. And calling him hidden isn't really the case, because in every stage there is a optional route where he can be encountered, and at one point I thought I would go the normal way but ended up fighting him without his weakness again. Combined with the fact that you so easily gain lifes from rescuing reploids and can't leave the stage, I had to be slowly defeated nine times to avoid losing the items I'd collected up to this point.

Speaking of optional routes, it didn't feel good to go those routes to get the items on it and then replay the first half of each stage again to go to the normal boss.

As for the difficulty level, I was confused at first as I didn't think the eight regular stages were that bad, but then came the final levels. Spikes everywhere, enemy spam everywhere, and a boss that you have to stun with the Charge Shot and then hit him with his weakness, which would be fine if it didn't take forever, and worse, the Charge Shot from one of the unlockable armors made his invincibility so janky that I couldn't hit him most of the time. The solution was to use a different Charge Shot the armor had, but it didn't feel right.

I'm scared of what awaits me in X7...

I knew people didn't like the second half of the X-franchise, but I didn't think it would go downhill so badly. X5 is a slog to play through and features some of the most unimaginative level design of any Mega Man title up to that point.
Of course, there are the annoying interruptions to explain obvious things that can't be turned off or even be skipped that make replaying this game, along with the unskippable cutscene, a torture.

I have the drive to 100% play all of these games, and in the previous four titles it was always fun to plan a route after the first playthrough to get all the items with the least amount of backtracking, but this game requires so much of it, I could hardly enjoy it.
A big offender is the water level with its three slow-scrolling sections and dialogue that you have to go to three times.

I also didn't like how the armor parts are handled, as you can only use them one once you found all four pieces, making finding a capsule much less rewarding. At least the Falcon armor is pretty good, too good, almost because of its flying ability, which might be the reason why you can't use it straight away, although they could give you the flying ability once you have all the parts, but use the other abilities if you find them.

And as if this game wasn't pace breaking enough, there are the bosses who are so spongy, especially in the rematches, that they're no fun to fight. I'm already not that big of a fan of Mega Man bosses who are completely outplayed by their weakness, but at least all of them die within seconds. Here you hit and stun them, wait for their invincibility to wear off, hitting and stunning them again and so on. It takes forever.

My first playthrough was with Mega Man and it was a miserable experience most of the time. Some enemies take way too many hits, most robot masters are too difficult to fight without their weaknesses and the level design can be infuriating, like cheap traps, the typical disappearing blocks but here they have inconsistent timing and the biggest annoyance are large rooms where you cannot see what is below or above you, so you may end up jumping into hazards sometimes instant-death ones.
And I played the Super Famicom version, I dont want to imagine how bad those parts are on the smaller GBA screen.

My second playthrough with Bass was a little more enjoyable. Mainly because I was familiar with the boss weaknesses this time and because of his double jump that makes some parts less frustrating. But it also makes others too easy.

If you don't feel the urge to play through the entire series like I did at the time of writing this, I'd say you can ignore this one or just play through it as Bass.