In the coming years probably starting with 004 they'll be constructing multiple carriers at the same time instead of constructing them one by one. So the speed will surely increase. By 2030s I think they'll have 10 carriers built. I doubt there will be economic consequence with Taiwan battle. UN recognizes Taiwan as a province of China, unlike the Crimea case which UN recognizes as a province of Ukraine. So even if China takes Taiwan by force there will not be sanction. Also, such a battle will likely be bloodless as in the case of Crimea battle. Taiwanese defenses will mostly surrender after the ultimatum.
Russia took back Crimea with a short battle. Azerbaijan took back Nagorno Karabakh with a short battle. China Taiwan battle will also be very short without a high body count before China takes back Taiwan.
It's pretty crazy to suggest that retaking Taiwan would be as east as annexing Crimea was. It's even crazier to put the 1.5 months long NKR war with thousands of dead, ballistic missile strikes against cities, and tens of thousands of troops actively engaged from both sides, in the same category as the relatively peaceful annexation of Crimea. I'm getting the idea that you literally have no idea what you're talking about. What short battle are you referring to in the taking of Crimea and how do you consider it at all comparable to the last NKR war? And what basis do you have for claiming that Taiwan would surrender after "the ultimatum"?
For the benefit of everyone else here the key factors that worked in Russia's favor when annexing Crimea were as follows;
1) Ukraine was economically doing significantly worse then Russia
2) Crimea had a majority ethnic Russian population,
unlike the rest of Ukraine
3) point #2 above caused significant tensions between Crimea with its local government, and the central government in Kiev, which Kiev handled extremely poorly, and Russia took advantage of this
4) Crimea was part of the same country with Russia as recently as 1991, within the living memory of the majority of its inhabitants
5) the institutions of statehood in Ukraine had decayed to an extreme point
6) the Ukrainian military and civil authorities in Crimea were largely sympathetic to a Russian takeover, likely more so then the population itself
7) there is a disparity of military power between Russia and Ukraine that made a full-on war a non-option for Kiev
8) while Crimea is a peninsula that Russia can only reach by water, the strait is extremely narrow and easy to cross, Russia already had a large military presence in Crimea, and the rest of Ukraine has a long and poorly defended land border with Russia
9) Ukraine's military had also decayed to a point where mustering large numbers of combat ready troops bordered on impossible
10) Ukraine had to deal with the possibility (a possibility that became a reality) of other pro-Russian uprisings
11) Russian and Ukrainian societies were not that different pre-2014, and many people travelled back and forth, had families on different sides of the border, and did business in both countries or across the border, becoming part of Russia did not mean an unthinkable change to regular life
None of these factors apply to Taiwan. Taiwan has been separate from China for much longer than 1991. The population of Taiwan does not appear to be sympathetic to a PRC takeover. The state institutions of Taiwan are functioning just fine. The government of Taiwan also does not appear to be sympathetic to a PRC takeover. Taiwan does not have an "external" threat from which it wants protection (the way Crimean authorities had with Kiev). Taiwan has a large and highly capable military that displays impressive combat readiness. Taiwan is separate from mainland China by a fairly wide strait, and there is no easy crossing into Taiwan. China does not currently have any military bases in Taiwan. China is a wildly different country from Taiwan in terms of society, culture, and economics. Integrating Taiwan would be either an extremely painful affair, or extremely slow (possibly both).
Realistically speaking its far from certain that the PRC would even manage to occupy and take over Taiwan as things stand now. They're certainly stronger, but Taiwan is not a small and isolated corner of the world. For all practical purposes it's a large country in its own right with economic and diplomatic ties to many other countries (even if these ties are sometimes less than official). Even with the situation in Ukraine, Russia only moved after an illegal change of government took place when armed rioters broken into the government quarter in Kiev, and president Yanukovich fled. I don't know enough about the internal politics of Taiwan to speculate on the possibility of such an event occurring, but its a rather special and particular circumstance.