Short answer. No. Article 1244 provides that a debtor cannot compel the creditor to receive a different thing, even if it is of the same value as, or more valuable than, what is actually due. The same rule blocks substituting a different act for one you promised to do or not do, without the creditor's agreement.
What the law says
The debtor of a thing cannot compel the creditor to receive a different one, although the latter may be of the same value as, or more valuable than that which is due. In obligations to do or not to do, an act or forbearance cannot be substituted by another act or forbearance against the obligee's will.
Civil Code, Article 1244 — No Substitution of the Prestation. Read the full provision →
Value is not the point
It is easy to assume that offering something more valuable than what is owed should satisfy any creditor. Article 1244 rejects that assumption directly: the debtor of a thing cannot compel the creditor to receive a different one, although the latter may be of the same value as, or more valuable than that which is due. The creditor bargained for a specific thing, and the article protects the creditor's right to insist on exactly that, regardless of how the substitute compares in market value.
The same principle applies to obligations to do or not do something
Article 1244 does not limit itself to obligations to deliver a thing. Its second sentence extends the same logic to obligations to do or not to do something: an act or forbearance cannot be substituted by another act or forbearance against the obligee's will. If you promised to perform a specific service or to refrain from a specific act, you cannot unilaterally swap in a different service or a different forbearance just because you consider it comparable or even better.
Consent changes the outcome
The article's restriction is framed around what the debtor can compel unilaterally; it does not prevent the creditor from agreeing to accept something else. If the creditor voluntarily agrees to receive a different thing, or to accept a different act or forbearance, that is a matter of the parties' consent rather than something Article 1244 forbids. What the article blocks is the debtor forcing the substitution over the creditor's objection.
What the article does not resolve
Article 1244 does not itself describe what happens when a creditor refuses to accept the thing that is actually due, as opposed to refusing a substitute — that is a different situation governed elsewhere. It also does not set out valuation methods or partial-performance rules. What it establishes cleanly is the core rule: your good intentions in offering an upgrade do not create a right to override what the creditor is actually entitled to receive.