For me, it's never too late. People must not look into the price of Bitcoin if they want to get introduced to Bitcoin. The goal of Bitcoin is to solve our current traditional problem, not the price or investment.
It still depends on your personal willingness to learn and adapt and if you really intend to invest then it is also depends on your financial position and risk tolerance.

For me, Bitcoin ETF could influence Bitcoin's price through various mechanisms.
Concerns about market manipulation are not unfounded, given the relatively unregulated nature of the cryptocurrency market.

Bitcoin spot ETF could potentially manipulate Bitcoin's price. Because at first, the essence of ETF which they can do trading easier and broader access to Bitcoin for both retail and institutional investors without need for them to hold the cryptocurrency directly.

Make sense, but you must separate the trading if you are looking forward in investing where the Dollar Cost Averaging (DCA) applies.
What if you keep losing in your trades but the one you hold keeps increasing the value, so more likely you  are making break even?

For me, trading in the spot market is cheaper fees than the futures market and less risk because in spot trading you only buy, no leverage, you can't short the market like the futures market.
About coins to avoid, I highly suggest trading pairs that have a high market cap or trading volume, so Bitcoin and Ethereum are the best pairs for this.

This is risky because not all cheap coins are good to invest in, some of them already lost their value by more than 90%.
So be careful, it's likely gambling.
You can relate this to buying the dip where even you can say it's already dip, you still can't guarantee if it will still dip.

https://www.coingecko.com/en/categories/modular-blockchain



As you can see this is from Coingecko categories for module blockchain and Celestia is the rank 1, no doubt, they are the first successful module blockchain right now.
But I believe there are already a lot of projects that are under development and will launch very soon, like Celestia, a modular blockchain.

Psychology is important in trading, crypto or non-crypto.
For example is a market cycle, which can be driven by psychological phenomena like greed, fear, overconfidence, etc. which can result in bubbles and crashes.

although psychology plays a significant role in cryptocurrency trading, it is not a massive barrier if you want to do trading.

I experienced "double dead" here when FTX & Terra Luna collapsed.
In despite of that, I moved forward and then strived more hard to get back those losses by trading, investing, and hunting hidden gems.

I am still hoping for an FTX Exchange refund like what most people do.

For me, there's no good and bad on diversifying or not diversifying.
Because your funds will be split into different asset so you have the chance to get lesser ROI while if you don't diversify and you got lucky on the 1 asset you invested, for sure you don't have to become stress to think other assets.

For me, I will go with high market cap altcoins if you want to have less risk, so Ethereum for me is the best right now.
If you want to find some gem and it will come with high risk high reward, you need to find newly launched altcoins with quality project, like maybe Top 300-500 and more.

I don't think that "quick profit" is the best term here, maybe high-risk high reward.

We all know how altcoins are volatile and risky since most altcoins out there are scams or just want to steal money from people.
It's essential for investors to conduct thorough research, consider the risks involved and have clear strategy while dealing with altcoins.

Seems fair, this pattern is already here even in previous bull seasons.
But before this will happen, I am expecting Bitcoin will outperform first altcoins, what I mean outperform is , we will see huge pumps for Bitcoin but for altcoins, they can go sideways and wait for Bitcoin to become stable.

3. Modular Blockchain - this is very new to the market, I will not be against this, but I can see there's still a lot of growth.

2. Spot Ethereum ETF - this is the most awaited for me. Just like Silver after Gold ETF. So I am expecting ETF Ethereum but we will need to wait longer.

I don't see any issue with OP because he wants the stablecoins and it just in the Tron network where we all know how cheap transactions are.
The Tron network got a huge Total Value Locked (TVL) in terms of Decentralized Finance (DeFi), they are the second biggest after the Ethereum network.

And add also that the hype in social media seems gone and starting to slow down compared to previous bull markets where you will see a lot of people or influencers who are luring these new people to trade just to get some commissions or affiliates and end up losing their hard-earned money.

Congrats OP.
Now your next assignment is how to become "diamond hands".
Where it will help you to keep calm, avoid FUDs, and panic sell.

If you have a plan to sell that stash in the future, avoid looking at Bitcoin prices from time to time. Go find some leisure to avoid looking at charts always 

For OP, I can suggest you look in the chart since the beginning and see or mark every block halving.
There you will see how the price moves before and after the Bitcoin block halving, and then you can decide.

Few years ago, I just found it out by my self and I waited years also to be ready in next Bitcoin block halving, now my speculation started to fulfil and going in right direction.

I don't think we will experience an "Exchange token narrative" this time but if yes, I am looking forward to KCS.
We all know Kucoin started, Kucoin has already been here for a long time and we have seen how they improved, it's just like it are underdog but with quality.

After most exchanges issue, people will start to find trusted one and for me Kucoin is one of them.

For me, we are in the middle of these.
What I am only positive about is we are already done in the accumulation period, we are now going in markup where we will start to attract more investors, retails, and institutional investors because once we experience this, for sure we will experience more high rally upward.

Not always, somethings that are happening are the opposite, sometimes yes.
For now, the market is already different, if Bitcoin pumps, altcoins pump, if Bitcoin dumps, altcoins dump, if Bitcoin stays sideways, altcoins pump.

But now it's totally different, like sometimes Bitcoin pump first then after a few days, altcoins especially Ethereum pumps. Or sometimes even Bitcoin already pumping altcoins or Ethereum still in sideways.